Percy Francis Westerman (1876 – 22 February 1959) was a prolific author of children's literature, many of his books are adventures with military and naval themes.
He was born in Portsmouth, England in 1876, and educated at Portsmouth Grammar School, before taking up a clerical appointment at Portsmouth Dockyard at the age of twenty. He married Florence Wager, of Portsmouth, in 1900. Always keen sailors, they spent part of their honeymoon sailing in the Solent. Their son, John F.C. Westerman, born in 1901, also wrote adventure books for boys.
At the age of 70 he was reluctantly forced by a fall to leave his houseboat for dry land, but he continued writing apace. He died at the age of 82, and his last book, Mistaken Identity, was published posthumously in 1959.
During the 1930s Westerman was voted the most popular author of stories for boys. His books sold over one and a half million copies in his lifetime (total sales at his death were 1, 599, 000). He published at least 174 books, with 12 different firms.