ISIS was founded in Iraq by Al-Qaeda and sunni rebels.

The war in Syria broke loose because global warming led to drought in Syria, which led to dying farms, which led to fear of an impending famine, which led to demands for more freedom, which led to a crackdown by the Assad-regime.
Putin has zero interest in Syria, apart from Syria allowing the russian fleet to use its ports in the Mediterranean Sea. And Putin only became involved when the war dragged on so long that this port-deal became endangered. Syria is mainly a lackey of Iran. The ties to Russia were thin before the civil-war.




And on the topic of global-warming kicking off the war... Climatologists have calculated that the whole region of the Persian Gulf will be so hot in 50-100 years, it will literally be almost uninhabitable for unprotected humans.
The UAE, Qatar, eastern and central Saudi-Arabia, Kuwait, southern Iraq, southern Iran. There will be massive heat there.