[1] Tiller's career started in 1931, when he became Norwegian amateur junior lightweight champion at the age of 17.

He rapidly grew to middleweight, where he became Norwegian champion in 1935, 36, 37, 38 & 40, before the second world war put a halt to further championships.

In 1936 he won the silver medal in the middleweight class after losing the final against Jean Despeaux.

He defeated Edward Peltz (RSA), Richard Shrimpton (GBR), the two favourites Adolf Baumgarten (GER), and Henryk Chmielewski (POL).

Later that same year Tiller met Despaux in two international championships in Trondheim and Oslo - both times defeating him.