Causes
On 15 July 1917 the Cadets walked out of the Russian Provisional Government, threatening the Mensheviks and the Socialist Revolutionaries (SRs) with the breakup of the government coalition. A government crisis was the result.
Anti-war feelings were rife among the populace at that time, due to the recently failed Galician offensive which had caused an estimated 200,000 Russian casualties. These feelings intensified with the news of the failed offensive. Discontented workers started protests which soon spiraled into violent riots.
Read more about this topic: July Days