In October of 1919, Denikin was launching his offensive on Moscow. While the Whites were not what one would necessarily call "unified," they were far from the splintered warlords they would become in 1920 and for the remainder of the war.
Wrangel had fairly solid control over the majority of White forces in Southern Russia/the Ukraine since his spat with Denikin hadn't yet flared up (it was by and large caused by the decisive failure of the Moscow campaign), and the same goes for Yudenich in the Baltics and Kolchak in Siberia. In fact, up until 1920, Kolchak was still officially regarded by Denikin, Wrangel, and Yudenich as the legitimate Commander-in-Chief of all White forces.
If Denikin is not betrayed by Makhno while he's en route to Moscow, or if he just decides not to send six regiments back to fight Makhno (which they never wound up doing, the anarchists basically having just pulled an ineffectual hit-and-run on Denikin's supply lines before the reinforcements could do anything about it), Denikin would most likely have defeated the Bolsheviks at the Battle of Oryol.
A White victory at Oryol means that the Bolsheviks are going to reconsider the forces they sent to beef-up Petrograd (which they had previously thought of abandoning and were only dissuaded by Trotsky ignoring their opinions and sending them anyways) and call them back to the capital. This means that Petrograd will fall to Yudenich and, even if the Red forces make it back in time, Moscow will probably fall to Denikin.
We should remember that in OTL, the Whites only really started to come undone after 1919 (corruption, drug abuse, arms-dealing, black marketeering, etc. were already endemic to the Whites, but not yet cripplingly so). The winter of 1919 is when Yudenich bowed out, basically leaving Whites in the Baltics and northwestern Russia without a leader. It's also the year that Denikin and Wrangel started fighting over what to do with their forces, a fight that would lead to Wrangel's resignation (and later brief re-installment) and Denikin and his cronies-cum-warlords grabbing land, wantonly looting, alienating Ukrainians with cultural chauvinism, and basically reversing all of the progress that the reform-minded Wrangel had initiated, thereby losing the support of most of the peasantry. And Kolchak? Well, he just got more and more autocratic when he realized he was the Whites' last chance at achieving anything. So there we have it. A White victory complete with all of the delicious butterflies that come with them still having refused to recognize Finnish and Polish independence.
The Whites win in late-1919-early 1920, something that is very, very plausible. A junta is established between Denikin, Wrangel, Kolchak, and Yudenich. It is decided that Wrangel becomes head of government (probably alongside Milyukov and Pepelyayev) while Denikin and Yudenich are put in charge of the military. Kolchak becomes an élément grise in Russian politics, sort of like a Hindenburg-Ludendorff mix; a figure given deference who sort of stays behind the scenes but is the man to call when "decisive measures" must be taken to reestablish "order."
Meanwhile, the near-universally beloved Grand Duke Nikolai becomes Tsar, though this time he is a constitutional monarch with negligible power at best. This not only satisfies traditionalists and democrats, but also provides the nation with an untainted figurehead that pretty much everybody can rally around.
After an ill-fated Russian experiment with parliamentary democracy à la pre-fascist Italy, Kolchak (at the urging of Grand Duke Cyril who ascends the throne in 1929) finally steps in to reestablish "law and order" and becomes the de facto dictator of Russia. People who present a threat to his new order like Denikin and Kutepov and much of the Army high-command will probably be purged.
Kolchak probably dies some time in the '30s. During and after his reign, movements like Aleksandr Kazem-Bek's Mladorossi gains momentum with its unique and popular (and typically fascist) slogans promoting both industrialization/modernization and traditionalism. Mladorossi or something with a similar name but in the same mold becomes the major (and eventually only) political party in Russia.
The charismatic and handsome Kazem-Bek becomes dictator after Kolchak kicks the bucket. How long his rule lasts is debatable due to his being of Azeri stock, but the major point is that his general philosophy of a social monarchy ("Tsar and the Soviets!") becomes the norm. His most likely successor is Anastasy Vonsyatsky (who may not be bigoted enough), or maybe Konstantin Rodzayevsky.
Ethnicities that will most likely be targeted under the Whites (and I'm assuming we have pre-WWII Soviet borders here) are Jews (of course), Poles, Gypsies, Ukrainians (i.e. people who regard themselves as "Ukrainians" rather than "Little Russians"), Volga Germans, Crimean Karaites, possibly Chinese, perhaps Finns, and maybe Azeris depending on if and how far Kazem-Bek falls. Obviously homosexuals and non-Orthodox will be persecuted, the only exception being Muslims. Also expect a great deal of anti-Western sentiment.
Caucasians and Central Asian tribesmen like Kazakhs and Kalmyks and Buryats and Turkmen will in all likelihood not be targeted for two main reasons; the anti-Bolshevism that the majority of these groups displayed, and the distinct lack of general anti-Tsarist sentiment amongst them. In fact, the tribesmen will probably join the Cossacks in the pantheon of "martial races" (excellent theory, RGB). Again, the fate of Azeris largely depends on the success or failure of Kazem-Bek.
Interestingly, the concept of "sophisticated secret policemen vs. partisan street thugs" like we see exemplified in the rivalry between the SS and SA already existed in Imperial Russia. The "sophisticated" aspect—the Okhrana—will be reestablished, expanded, and revitalized under the leadership of people like Mikhail Diterikhs. The "street thug" element will lie in the resurrected Yellow Shirts under the command of somebody like Lev Okhotin or Gen. Vladimir Kozmin.
Another thing of note is the viability of Konstantin Rodzayevsky as the successor to basically any post. Head of the Okhrana, head of the Yellow Shirts, even Vozhd (or whatever the head honcho spot is called); Rodzayevsky could potentially succeed to any one (or perhaps even two) of these positions.
Basically, the regime we get is a cross between Iron Guard Romania and Francoist Spain alongside some major elements of clerical fascism.
Wrangel had fairly solid control over the majority of White forces in Southern Russia/the Ukraine since his spat with Denikin hadn't yet flared up (it was by and large caused by the decisive failure of the Moscow campaign), and the same goes for Yudenich in the Baltics and Kolchak in Siberia. In fact, up until 1920, Kolchak was still officially regarded by Denikin, Wrangel, and Yudenich as the legitimate Commander-in-Chief of all White forces.
If Denikin is not betrayed by Makhno while he's en route to Moscow, or if he just decides not to send six regiments back to fight Makhno (which they never wound up doing, the anarchists basically having just pulled an ineffectual hit-and-run on Denikin's supply lines before the reinforcements could do anything about it), Denikin would most likely have defeated the Bolsheviks at the Battle of Oryol.
A White victory at Oryol means that the Bolsheviks are going to reconsider the forces they sent to beef-up Petrograd (which they had previously thought of abandoning and were only dissuaded by Trotsky ignoring their opinions and sending them anyways) and call them back to the capital. This means that Petrograd will fall to Yudenich and, even if the Red forces make it back in time, Moscow will probably fall to Denikin.
We should remember that in OTL, the Whites only really started to come undone after 1919 (corruption, drug abuse, arms-dealing, black marketeering, etc. were already endemic to the Whites, but not yet cripplingly so). The winter of 1919 is when Yudenich bowed out, basically leaving Whites in the Baltics and northwestern Russia without a leader. It's also the year that Denikin and Wrangel started fighting over what to do with their forces, a fight that would lead to Wrangel's resignation (and later brief re-installment) and Denikin and his cronies-cum-warlords grabbing land, wantonly looting, alienating Ukrainians with cultural chauvinism, and basically reversing all of the progress that the reform-minded Wrangel had initiated, thereby losing the support of most of the peasantry. And Kolchak? Well, he just got more and more autocratic when he realized he was the Whites' last chance at achieving anything. So there we have it. A White victory complete with all of the delicious butterflies that come with them still having refused to recognize Finnish and Polish independence.
The Whites win in late-1919-early 1920, something that is very, very plausible. A junta is established between Denikin, Wrangel, Kolchak, and Yudenich. It is decided that Wrangel becomes head of government (probably alongside Milyukov and Pepelyayev) while Denikin and Yudenich are put in charge of the military. Kolchak becomes an élément grise in Russian politics, sort of like a Hindenburg-Ludendorff mix; a figure given deference who sort of stays behind the scenes but is the man to call when "decisive measures" must be taken to reestablish "order."
Meanwhile, the near-universally beloved Grand Duke Nikolai becomes Tsar, though this time he is a constitutional monarch with negligible power at best. This not only satisfies traditionalists and democrats, but also provides the nation with an untainted figurehead that pretty much everybody can rally around.
After an ill-fated Russian experiment with parliamentary democracy à la pre-fascist Italy, Kolchak (at the urging of Grand Duke Cyril who ascends the throne in 1929) finally steps in to reestablish "law and order" and becomes the de facto dictator of Russia. People who present a threat to his new order like Denikin and Kutepov and much of the Army high-command will probably be purged.
Kolchak probably dies some time in the '30s. During and after his reign, movements like Aleksandr Kazem-Bek's Mladorossi gains momentum with its unique and popular (and typically fascist) slogans promoting both industrialization/modernization and traditionalism. Mladorossi or something with a similar name but in the same mold becomes the major (and eventually only) political party in Russia.
The charismatic and handsome Kazem-Bek becomes dictator after Kolchak kicks the bucket. How long his rule lasts is debatable due to his being of Azeri stock, but the major point is that his general philosophy of a social monarchy ("Tsar and the Soviets!") becomes the norm. His most likely successor is Anastasy Vonsyatsky (who may not be bigoted enough), or maybe Konstantin Rodzayevsky.
Ethnicities that will most likely be targeted under the Whites (and I'm assuming we have pre-WWII Soviet borders here) are Jews (of course), Poles, Gypsies, Ukrainians (i.e. people who regard themselves as "Ukrainians" rather than "Little Russians"), Volga Germans, Crimean Karaites, possibly Chinese, perhaps Finns, and maybe Azeris depending on if and how far Kazem-Bek falls. Obviously homosexuals and non-Orthodox will be persecuted, the only exception being Muslims. Also expect a great deal of anti-Western sentiment.
Caucasians and Central Asian tribesmen like Kazakhs and Kalmyks and Buryats and Turkmen will in all likelihood not be targeted for two main reasons; the anti-Bolshevism that the majority of these groups displayed, and the distinct lack of general anti-Tsarist sentiment amongst them. In fact, the tribesmen will probably join the Cossacks in the pantheon of "martial races" (excellent theory, RGB). Again, the fate of Azeris largely depends on the success or failure of Kazem-Bek.
Interestingly, the concept of "sophisticated secret policemen vs. partisan street thugs" like we see exemplified in the rivalry between the SS and SA already existed in Imperial Russia. The "sophisticated" aspect—the Okhrana—will be reestablished, expanded, and revitalized under the leadership of people like Mikhail Diterikhs. The "street thug" element will lie in the resurrected Yellow Shirts under the command of somebody like Lev Okhotin or Gen. Vladimir Kozmin.
Another thing of note is the viability of Konstantin Rodzayevsky as the successor to basically any post. Head of the Okhrana, head of the Yellow Shirts, even Vozhd (or whatever the head honcho spot is called); Rodzayevsky could potentially succeed to any one (or perhaps even two) of these positions.
Basically, the regime we get is a cross between Iron Guard Romania and Francoist Spain alongside some major elements of clerical fascism.