The Indianapolis streetcar strike of 1913 and the subsequent police mutiny and riots was a breakdown in public order in Indianapolis, Indiana. The events began as a workers strike by the union employees of the Indianapolis Traction & Terminal Company and their allies on Halloween night, October 31, 1913. The company was responsible for public transportation in Indianapolis, the capital city and transportation hub of the U.S. state of Indiana. The unionization effort was being organized by the Amalgamated Street Railway Employees of America who had successfully enforced strikes in other major United States cities. Company management suppressed the initial attempt by some of its employees to unionize and rejected an offer of mediation by the United States Department of Labor, which led to a rapid rise in tensions, and ultimately the strike. Government response to the strike was politically charged, as the strike began during the week leading up to public elections. The strike effectively shut down mass transit in the city and caused severe interruptions of statewide rail transportation and the 1913 city elections.

A riot that lasted four days broke out on November 2 when strikebreakers attempted to restart transit services. At its height, eight to ten thousand rioters flooded downtown Indianapolis and vandalized the city's main business district. Numerous workers, strikebreakers, policemen, and bystanders were injured. Two strikebreakers and four union members were killed. The city police were unable to control the situation and refused orders to combat the rioters as the violence worsened. After pleas for help from city leaders following continued rioting on Election Day, Governor Samuel Ralston called out the Indiana National Guard and put the city under martial law on the evening of November 5.

On November 6, an angry crowd surrounded the Indiana Statehouse, listed their grievances, demanded the military leave the city, and threatened more violence if their demands were not met. Ralston addressed the crowd to promise concessions if the workers would return to work. His speech was credited by the press with ending the strike. After three days of peace, the military withdrew from the city. The Indiana General Assembly met later that month and enacted Indiana's first minimum wage laws, regular working hours, workplace safety requirements, and began projects to improve the city's tenement slums.

Arbitration between the company and its employees by the Indiana Public Service Commission resulted in a decision mostly favoring the company. The employees were permitted to unionize, guaranteed wage increases, a minimum monthly salary, and certain days off work. The company, however, was permitted to continue hiring non-union employees and to bar union membership solicitation on the company's property.