Bell Labs — and ETH Zürich, where Robert Griesemer worked as a PhD student under Niklaus Wirth on Oberon, which had a big influence on Go [1].

The earlier languages that Rob Pike et al were involved with, Limbo and Newsqueak, were also heavily influenced by Wirth.

[1] https://talks.golang.org/2015/gophercon-goevolution.slide#15.