This wasn't the year Donald Trump burst into the public consciousness, nor was it the year Trump got political — he's had presidential ambitions since at least 1999. Rather, 2015 was the year Donald Trump held the Republican Party hostage, and the rest of America captive.

Political conditions were ripe for a Trump candidacy this year. His trademark combination of big promises and vague gesturing at threats from Mexican immigrants and Syrian refugees inspired hope in the hearts of disaffected Republicans, and fear in the hearts of everyone else, including the leadership of his own party. It was the year that — against all odds, and despite all predictions — Trump has remained stubbornly atop Republican primary polls.

Here were his key moments of the year.