He was born in Edinburgh, Scotland, on March 10, 1832 the youngest of 11 children, his siblings including brothers George, James, John, David, Robert, and William; plus sisters Euphemia, Jane, Grace, and Janet.
In 1869, he was elected California State Controller, an office he held for four years.
Watt was officer or director of several institutions, including the Union Trust Company,[4] the San Francisco Savings Union,[5] the Wells Fargo Nevada Bank (merger of Wells Fargo with the Nevada Bank of San Francisco),[6] and the Langley & Michaels Company.
[1] He married Elizabeth Dewey Leighton in 1863, establishing their home in Grass Valley, California.
[7] Watt was a member of the Bohemian, University, and Pacific Union clubs.