Protesters wore masks and kept their distance to comply with coronavirus restrictions.
Thousands of people formed a human chain in Berlin on Sunday to speak out against racism and social inequality.
Organisers said at least 20,000 people gathered in the German capital to form the chain, which stretched nine kilometres from the Brandenburg Gate to Neukoelln, a neighbourhood in south-eastern Berlin. Police put the number at 5,000.
Protesters, who had been told wear masks and keep apart, were joined together by what the alliance described as a "ribbon of solidarity".
Smaller demonstrations were also held in several other cities in Leipzig and Hamburg, the latter of which was attended by 2,500 people, organisers said.
The alliance said in a statement that the day of action was "to send a clear signal for a gender-fair, climate-friendly, social and anti-racist society".
Spokesperson Georg Wissmeier stressed that "the corona(virus) crisis exacerbates existing inequalities. Many risk being left behind."
Berlin recently lifted coronavirus-related limits on the number of people who can attend demonstrations but social distancing measures are still enforced, including the requirement to keep at least 1.5 meters apart in public.
At least 15,000 people attended an anti-racism protest in Berlin last weekend, in some cases closely packed together, drawing criticism from officials.
It was one of many demonstrations worldwide in the aftermath of the May 25 death of George Floyd, who died after a white Minneapolis police officer pressed his knee to his neck.