The forename Winston is one used principally by the Churchill family, of Blenheim Palace, most famously by Winston Churchill, the British Prime Minister during the Second World War. It is rare enough for it to be rational for him to be known by the public at large simply as Winston, occasionally Winnie.
The Churchill family derive it from the maiden name of Sarah (d. in or before 1657), daughter of Sir Henry Winston, who married John Churchill (c.1587–1659). Their second (but first surviving) son, Winston (c.1620-1688), knighted in 1664, was baptized on 18 April 1620. He was the father of John Churchill, the famous 1st duke of Marlborough.
The fictional hero of George Orwell's novel 1984 is called Winston Smith, presumably uniting a forename given in honour of the great hero of British life as Orwell was writing, the war leader and Prime Minister Winston Churchill rather bathetically with the most common surname in Britain.