There was global outrage when Vladimir Putin ordered the full-scale invasion of Ukraine.
However, the barbaric act was not the first time Putin had ordered troops to encroach on the sovereign lands of neighbouring nations, with the annexation of Crimea taking place in 2014.
Now, as he holds a pro-war rally in Moscow today to mark eight years since the annexation, it appears that Putin may have expected the invasion of Ukraine to go a little more smoothly.
So far, Russian troops have failed to take major cities like Kharkiv and the capital Kyiv, and it's proved to be far less easy than the sweeping annexation of Crimea in 2014. Ukrainian troops are putting up fierce resistance despite the indiscriminate bombing of civilians by Putin's forces.
So where is Crimea and who does it belong to?
What happened in Crimea?
Russia invaded Crimea and took it over in 2014, amid political unrest in Ukraine.
The Crimean Peninsula was conquered by Russian empress Catherine the Great in the 18th century but it became part of Ukraine in 1954 when the Soviets decided to move its jurisdiction to Ukraine.
After the collapse of the Soviet Union in 1991, Ukraine gained independence and Crimea remained part of its territory, though most of the population are ethnically Russian and it is the majority language.
Its location on the Black Sea means that it is of strategic importance for Russia - and its navy in particular - and Ukraine and Russia used to share the port of Sevastopol.
After 2012, Putin began to shift the focus of Russian politics to even more of an anti-Western stance and these populist policies remain today.
Nationalistic policies, such as the idea that the West is an aggressor against Russia, and that Ukraine and Belarus should be part of Russia, make it easy for Putin to score points among his support.
In 2014, the 'Revolution of Dignity' took place in Ukraine, in which the country got rid of its corrupt, Russian-aligned government. From this point, Ukraine began to side more with Western policy and looked to join the European Union and NATO.
Putin moved to annex Crimea after the pro-Russian government in Ukraine fell that same year. Six people were killed during the annexation.
Afterwards, the Russian leader began supporting separatists in Eastern Ukraine, who also believe that parts of Ukraine should be in Russia.
Is Crimea in Russia or Ukraine?
Whether Crimea is in Russia or Ukraine is a matter of political opinion, though it is quite clearly now under Russian control.
Most countries continue to recognise Crimea as being part of Ukraine and the US refused to recognise Russian control before the invasion earlier this year.
In March 2014, a referendum was held that voted overwhelmingly in favour of Russian control of Crimea. However, the opposition boycotted the vote and the result was not recognised by the United Nations.
The West imposed sanctions on Russia as a result of its actions there, but this had little effect.
Ethnic cleansing in the region took place under Jospeh Stalin, who removed the Crimean Tatars, confiscating their lands and deporting them to central Asia.
They were allowed to return after Ukrainian independence, but the population is now majority Russian.
