Trump’s 2016 election has sparked a major upsurge in protest in the U.S. Bringing together a diverse set of issues and constituencies, activists have organized thousands of protests with over six million participants in the year following the inauguration. Additionally, more than five thousand local organizations have been established by the anti-Trump Indivisible mobilization network. I draw on protest event data to track the main issues and claims at the forefront of the movement. Second, I examine the local patterning of mobilization focusing on the role of prior movement activity, partisan political dynamics, and lifestyle politics as major drivers of movement mobilization. Building on the analyses, I draw implications for theories of protest, movements, and politics and possible lessons for the future of activism during the Trump presidency.