Has your nation ever changed it's system of government?

[Radiatia]

Yes. The first attempt to unify the various former kingdoms and nations of Radiatia was the United Socialist States of Radiatia - you guessed it, a socialist country (albeit a very democratic form of socialism), which consisted of just seven states.

Then came a coup by hardline nationalists who proclaimed the "Radiatian Empire", effectively a fascist regime, and rapidly expanded Radiatia's borders. Following this was a civil war between nationalists and communists, with the latter victorious and beginning the years of the infamous Radiatian People's Socialist Union (RPSU).

Finally, communism broke down and pro-democratic forces overthrew the regime, which led to the creation of the modern Radiatian Federation.

However, the Radiatian Federation has changed its constitution (via popular referendum) three times, thus changing the system of government. Initially it as a Semi-Presidential Republic until the signing of the Second Constitution made it a Parliamentary Republic.

This system broke down after the Radiatian Constitutional Crisis leading to the signing of the third and current constitution, which made the Radiatian Federation a Presidential Republic.

[Sleet Clans]

Yes. When the Clans united we were originally a representative republic, with a leader from each of the five former Clans in a sort of 'council'. However, this meant that barely anything could be got done due to argueing. After a hundred years of this system, the council was dissolved and the chieftan-king of the monarchy was head of the country. This remained during Sleetavia's short colonial period in the early to late 1600s, however during the reign of Chieftan-King Mersken VIII from 1780-1801, the people got sick of his corrupt reign and overthrew him. They executed Mersken VIII himself, but his children survived and thus Sleetavia's monarchy survives to this today. Of course, today they are merely figureheads for the public, and have redeemed themselves from the actions of Mersken VIII by providing moral support to the people of the Clans in times of need.

Today, the Clans are united under a President, and are classified as a United Confederacy. Elections are every 8 years. However, back in 2012 a military coup temporarily exiled the then President Zòul Emesh, but this coup's reign only lasted for 5 and a half weeks before loyalist forces regrouped and retook Silçka. The President was restored to power and the Confederacy continued being a democracy.

[Blorbs]

Yep, 1902 peacful revolution. Along with a more socialist government, it converted Blorbs from a republic to pave the way for direct democracy. Originally the people only voted on national legislation after the 1902, and most people didn't have the time anyway, but as technology advanced elecronics were used to make it extremely simple for civilians to propose laws and edicts, and for almost everyone to have the time to vote on Bills at both national and provincial levels.

[Vallermoore]

First we were a Queendom, but after one of the Queens went insane and kidnapped several people's daughters and the Queen after that let crime get out of control, we became a democracy. After we voted in the Megatronist Party, there are rumours that we might become a dictatorship.

[Dragos-Land]

No. Dragos-Land was and forever will be a corrupt fascist one-party nation.

[Kazarogkai]

Since unification there's been a few mainly in the form of how the central government operates. When unification was achieved the Initially began more or less as a federation of city states under the heel of a monarch. Though somewhat originally feudal the Kaza established a system mirroring that of china's mandarins leading to the rise of a civil and military bureaucratic class known as the Rasa which with time mostly comprised commoners rather than members of the nobility.

Despite this or because of this fact the government became increasingly centralized with power concentrated in the hands of the highest nobility derived mostly from what were known as the court nobles who unlike the Country nobles lacked land but instead derived pay in the form of higher offices and direct supplements from the monarchs coffers in exchange for service. With the use of the Rasa as their on the ground guys they were able to replace the need for and marginalize the lower nobility or country nobles as they were known as. This led to a rather volatile situation which ultimately resulted in a war known as the "Confederate Wars" which sought to return local power and the ancient privileges of lower nobility.

The Central Government's victory in this long and bloody war resulted in an increased reliance on the Rasa which ultimately led to it's doom for during this conflict they became radicalized. Though originally content with their position they grew angry with what they regarded as a grave injustice in the form of their lower status. Though the nobles desperately relied on them to hold onto power just because of the way they were born they were regarded as lessers and shut out from true positions of power to forever serve as lackeys to the Nobles. Unlike the Rasa who earned their positions the Nobles gained it as a consequence of birth which didn't settle well with the Rasa at all.

Not too long after the "Confederate Wars" more conflict would grace the Lands of the Kaza. The outbreak of the "Rasa War" which resulted in the aforementioned's victory led to the overthrow of the monarchy and the nobility in general and creation of what was in effect a Republic with proto-socialist undertones. The reason for that was because in order to gain a source of soldiers the Rasa promised to end slavery/serfdom and bring about land reform for the masses along with other things which they ended up mostly carrying out.

As such the timeline goes sorta like this:

Tribal
City-states
Feudal Monarchy/Federation
Bureaucratic Monarchy
Stratocratic Republic

[Welskerland]

Sorta. Welskerland has always been a monarchy since it was first created, but the monarchy changed in the way it governed. The kingdom was an absolute monarchy until 1878 when King Darreld II ruled tyrannically and the military turned against him. He surrendered to the military and was placed under house arrest until he signed the constitution, making Welskerland a constitutional monarchy.

[Autonomous Eastern Ukraine]

When we went from Soviet Socialist Republic, to the short lived Republic of Ukraine and finally to the Federation of Eastern Ukraine.

[Emericia]

Unknown to 1948 - Emericia consisted of 115 different kingdoms.
1949 to 1951 - The Kirov revolution occurred, where a dictatorship of the proletariat was established to inspire revolution across the Emerician kingdoms.
1951 to present - Executive and legislative power was handed over to the premiers office and the Proletariat's Congress respectively, as part of the Emerician Unification. Emericia was established as a Democratic Communist Republic.

[Alinghi Federal-Democratic Republic]

1750-1789 - Absolute Monarchy
1789- 1887 - Parliamentary Republic
1887-1899- Presidential republic
1900-1931 - "Lost Indipendence"
1932-2003 - Parliamentary Monarchy
2004 Absolute monarchy
2004-2040- Parliamdntary Republic (called as First Republic)
2041-2156- President Republic (called as Second Republic)
2156-xxxx - Semi presidential Republic (called as Thind Republic)

[Avinaa]

Avinaa has gone through a few changes in government.

564BC-900AD: Kingdom(tribal unions)
Chief Executive: King
Legislature: Tribal Councils
900AD-1414 Republic(Roman Confederation)
Chief Executive: Co-Consuls
Legislature: Senate(de-facto), House of Assembly(de-jure)
1414-1418 Dictatorship
Chief Executive: Military Council
Legislature: None
1418-1551 Tanor Family Dynasty(Kingdom of Rome)
Chief Executive: King
Legislature: Privy Council
1551-1553 First Civil War
Chief Executive: Disputed
Legislature: none
1553-1773 Fatta Family Dynasty(Avinaain Empire)
Chief Executive: King-Emperor
Legislature: Imperal Privy Council
1773-1801 Constitutional Monarchy(Kingdom of Avinaa)
Chief Executive(s): King-Emperor(de-jure), Prime Minister(de-facto).
Legislature: Parliament
1801-1804 Military Dictatorship
Chief Executive: King(de-jure), Military High Command(de-facto)
Legislature: none
1804-1810 Transitional Administration(Republic of Avinaa)
Chief Executive: Chief of State
Legislature: Interim National Assembly
1810-1814 Second Civil War
Chief Executive: Disputed
Legislature: none
1814-1900 Aviniaan Confederation
Chief Executive: Chief of State
Legislature: Confederate Congress
1900-1920 Presidential Republic
Chief Executive: President
Legislature: Federal Congress
1920-1954 Fascist Dictatorship(1928-1945 Third Civil War; 1920-1954 insurgency)
Chief Executive: President-for-Life
Legislature: Popular Assembly(de-jure), Quorum of Thirteen(de-facto), Ruling Council(de-facto)
1954-1956 Transitional Administration
Chief Executive: Interim President
Legislature: National Transitional Council(de-jure), National Dialogue Conference(de-facto)
1956-1975 Presidential Republic
Chief Executive: President
Legislature: Federal Congress
1975-present Semi-Presidential Parliamentary Republic
Chief Executive: President, and Prime Minister
Legislature: Federal National Assembly