Augustus S. "Squire" Ensworth (1810 – September 13, 1865) was an American politician who served as a member of the California State Assembly, representing the 1st District from 1859 to 1860.

He settled in Goliad where he was elected as chief justice in January 1840, resigning from the post to become a commissioner by the end of the month.

[3] In 1856, he became a justice of the peace for San Diego, and in 1859 was elected as a member of the California State Assembly for the 1st district.

In 1863, he filed a claim for a 160-acre ranch that included Spring Valley, where he built an adobe house that was later sold to Rufus King Porter and later to historian Hubert Howe Bancroft.

[7] On September 13, 1865, he died from an infection, with judge Benjamin Ignatius Hayes informing Whaley about his death.