The Russian invasion of Ukraine in February 2022 sparked protests around the globe. Most of Europe had – luckily – not seen violent conflict of this scale on their doorstep for more than 30 years. For Germany, the period was even longer. Being confronted with news about the war drove thousands of German citizens to the streets. In passionate protests, they made various demands of their government. Herein, we investigate the links between Germans’ emotions and their readiness to engage in such protests. Drawing on collective action research, we predicted that anger and sympathy would correlate positively with Germans’ protest readiness. Given the context and public debate, we predicted that fear should also correlate with protest readiness. Two surveys (total N = 905) conducted with residents of Germany – one day after the invasion and at its first anniversary – supported our hypotheses. We consistently found that the more sympathy and anger respondents experienced, the greater their readiness to protest. Fear explained variance beyond sympathy and anger in two cases and in an information-seeking measure of protest readiness: Greater fear correlated with a higher interest in demonstrations advocating peace negotiations and a lower interest in demonstrations calling for solidarity with Ukraine. These findings underscore the links between sympathy, anger, fear, and the readiness to protest in response to the contemporary crisis that is the war in Ukraine.