He was awarded the Davy Medal in 1952 "In recognition of his researches into the chemistry of natural products, particularly the wide range of glycosides, bitter principles and colouring matters containing heterocyclic oxygen atoms".
During World War I, he served in the Special Brigade, Royal Engineers (1916) and in the 2nd Seaforth Highlanders (1917), achieving the rank of lieutenant before being discharged in 1918.
After completing his Ph.D., Robertson moved to the University of Manchester to work with Robert Robinson (chemist) on a Rockefeller International Science Fellowship (1924-1926).
He moved on to a position as Assistant Lecturer in Chemistry at University of Manchester in 1926, where he contributed to "synthetic work on anthocyanidin and anthocyanin pigments, identification of alkaloids of morphine and strychnine, and the Lapworth-Robinson electronic theory of organic reactions.
Some of his notable trainees include Francis M. Dean, H. Gobind Khorana (1948), and William Basil Whalley (1952).