It was created in 1961, together with the subsidiary title of Viscount Linley, of Nymans in the County of Sussex, by Queen Elizabeth II for her then-brother-in-law, Antony Armstrong-Jones,[2] who married Princess Margaret in 1960.

Snowdon, chosen for the earldom, had previously been used for a peerage title with royal associations.

[3] Nymans, chosen as territorial designation of the viscountcy, relates to an English garden near Handcross in West Sussex, where Anne Armstrong-Jones, née Messel, Countess of Rosse, mother of the 1st Earl of Snowdon, had grown up.

[3] In November 1999, the 1st Earl of Snowdon received a life peerage as Baron Armstrong-Jones,[4][5] under a device designed to allow first-generation hereditary peers to retain their seats in the House of Lords, after the passing of the House of Lords Act 1999.

The heir apparent is the present holder's only son, Charles Armstrong-Jones, Viscount Linley (b.