Mount Brewster is a part of the Southern Alps, and lies at the end of the Young Range.

[2] Mount Brewster is formed from sedimentary rock layers, primarily sandstone, siltstone and mudstone.

The rock dates from the Middle Permian and Triassic periods, and was formed approximately 201–273 million years ago.

[3] Julius von Haast named the peak after Scottish physicist David Brewster.

[4] The first ascent of Mount Brewster was made in January 1929 by Samuel Turner, Eric Miller, Charles Bentham and C.