Go is influenced by several languages, and Modula and Oberon are at the top of that list. Robert Griesemer, one of the designers of Go, worked on Oberon at ETH Zürich.

Yes. The GoPL book has a diagram of Go influences (languages) near the start of the book.

The famous "Why Pascal is Not My Favorite Programming Language" article was written by Brian Kernighan, not by Ken Thompson (who created Go). Kernighan wrote the books about C and Go.