In 1907, shortly after the disastrous S.F. earthquake, streetcar workers went on strike against United Railroad (URR) demanding a eight hour workday and a salary hike. URR immediately brought in strikebreakers along with armed guards rather than negotiate with the strikers.
When URR attempted to run the streetcars staffed by strikebreakers, strikers and sympathisers threw stones and blocked the road. In response, armed strikebreakers began shooting into the crowd. Pitched battles where fought throughout the city with riotous masses pelting the cars with stones and bricks and the strikebreakers shooting back. At one point strikers took over an abandoned streetcar and sent it crashing into the barracks where the strikebreakers slept. By the end of the first day three where dead and over a dozen where wounded, mostly strikers and their sympathisers.
The battles and sabotage continued for nearly four months with many more casualties. In the end URR broke the strike, but the savage tactics of the company left the city bitter. In 1912 a popular movement for a publicly-owned streetcar line pushed URR out of S.F.
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