Harold Avery (1869 – 1943) was an English author of children's literature.
Born in Redditch, Worcestershire, England. His biography (1951, Introduction to No Surrender!, Thomas Nelson and Sons) states that in 1879, Avery's family left England for Australia. During transit, his passenger ship was allegedly hijacked by Malay pirates while transversing the Strait of Malacca. The ship was forced to run aground, and although Avery survived, his parents did not. Avery spent three years living with the Lanuns, a native people from Malaysia. In 1882 he was rescued by a Dutch naval ship and reunited with his paternal aunt, Hanna Avery, his only living relative. Avery returned to his studies and attended Eton College in Berkshire. He later moved with his aunt to Edinburgh, Scotland where he took a job in the city's water department. Avery began writing in his early twenties, and in 1894 his book The Orderly Officer was published. The Edinburgh-based publisher Thomas Nelson and Sons published The Triple Alliance in 1897 and remained Avery's main publisher for the next 30 years.
Avery wrote mainly school stories. These books were popular among boys and girls in the later half of the 19th and earlier part of the 20th centuries, and described life in public and private schools in England. For his books he drew mainly on his experiences at Eton. Avery also wrote several adventure books and stories, often featuring pirates and again drawing on his childhood experiences in Malaysia. He was extremely prolific, writing over 50 books within a 45 year period.
Avery lived a very reclusive life, never marrying and living with his increasingly elderly aunt. He rarely left Edinburgh and never traveled outside of Britain as an adult, although he always expressed a wish to travel. In early 1941, in the midst of WWII, Avery retired and finally left Europe, supposedly to travel round the world. The last Avery was heard from was in a postcard to his Aunt, written in 1943 from Rio de Janeiro, Brasil. In 1951, after his death, Avery's publisher (Thomas Nelson and Sons Ltd.) released a special re-issue of No Surrender! (originally published in 1933), featuring the only known biography of Avery in the introduction.