Sir William John Polson was a New Zealand politician, first as an Independent and then in the National Party. He joined the National Party on its formation in 1936, and "later acted effectively as Holland's deputy".

The New Zealand National Party, shortened to National or the Nats, is a centre-right New Zealand political party that is the current ruling party. It is one of two major parties that dominate contemporary New Zealand politics, alongside its traditional rival, the Labour Party.