Sure, the most significant factor is probably the annexation of Crimea. The current government in Russia says they wanted to protect their population in Crimea from a perceived threat, but many people say it was a land grab.
assistant
Russia thinks it has the right to a large chunk of Ukraine. They also want to keep Ukraine from joining NATO, and they want to keep Ukraine from aligning with the West.
assistant
Can you tell me why Russia wants to invade Ukraine?
user