Walpole's father secured for him three sinecures which afforded him an income: in 1737 he was appointed Inspector of the Imports and Exports in the Custom House, which he resigned to become Usher of the Exchequer, which gave him at first £3900 per annum but this increased over the years. Earlier biographers, such as Lewis, Fothergill, and Robert Wyndham Ketton-Cremer, interpreted Walpole as asexual.

Biographers such as Timothy Mowl explore his homosexuality, including a passionate but ultimately unhappy love affair with the 9th Earl of Lincoln.

Many contemporaries described him as effeminate (one political opponent called him 'a hermaphrodite horse'). He never married, engaging in a succession of unconsummated flirtations with unmarriageable women, and counted among his close friends a number of women such as Anne Seymour Damer and Mary Berry named by a number of sources as lesbian. His sexual orientation has been the subject of speculation. Walpole did not have any serious relationships with women he has been called 'a natural celibate'. the whole of his psychological history was dominated by it'. According to one biographer, his love for his mother 'was the most powerful emotion of his entire life. Ceasing to reside at Cambridge at the end of 1738, Walpole left without taking a degree. Walpole came to accept the sceptical nature of Middleton's attitude to some essential Christian doctrines for the rest of his life, including a hatred of superstition and bigotry even though he was a nominal Anglican. Īt Cambridge, Walpole came under the influence of Conyers Middleton, an unorthodox theologian. More important were another group of friends dubbed the 'Quadruple Alliance': Walpole, Thomas Gray, Richard West, and Thomas Ashton. At Eton he formed a schoolboy confederacy, the 'Triumvirate', with Charles Lyttelton (later an antiquary and bishop) and George Montagu (later a member of parliament and Private Secretary to Lord North). Walpole's first friends were probably his cousins Francis and Henry Conway, to whom he became strongly attached, especially Henry. He was also educated at Eton College and King's College, Cambridge. Like his father, he received early education in Bexley in part under Edward Weston. Walpole was born in London, the youngest son of British Prime Minister Sir Robert Walpole and his wife, Catherine.

The castle of otranto by horace walpole