(CNN) On this week more than 150 years ago, dozens of Native American men were killed by the government in the largest mass execution in US history.

In the Dakota War of 1862, also known as the Sioux Uprising, groups of Dakota (part of the Sioux group of Native American tribes) were angry with the US government over broken land treaties and late annuity payments. Times were tough, too, and Dakota families were starving.

A lithograph from 1883 depicting the execution of the 38 Dakota Indians at Mankato, Minnesota, December 26, 1862.

Dakota natives went to war against white settlers in Minnesota, which had just become a state four years prior.

The uprising ended on December 26, when 38 Dakota natives were hanged in Mankato, Minnesota, in a mass execution. The remaining natives were forced to leave Minnesota -- at first being held at a camp and then being sent out of the state.

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