The Clematis was first introduced in the UK way back when in the 1830s... now a relic from an imperialist age, when the UK's plant hunting trade was truly in vogue. Clematises, Geraniums, and Lupins all came to the UK in ships; with plant hunters pillaging plants from across the globe, all for a growing demand back home in Victorian Britain, for bright and blousy flowers from far off lands.
The Clematis Montana is no different, and originates from India, with Lady Amherst, wife of the retired Governor-General of India, bringing the variety back to the UK in 1831. It was described by Paxton's Magazine of Botany in 1840, when it was a relatively new addition to British gardens, as a "showy... charming" addition to the British garden, with a brilliant display of "snow white" and "delicate pink" blossoms. Nearly 180 years later, it is still a regular feature in the garden, and it is easy to see why; a sprawling mass of flowers, providing colour and fragrance in early Spring, and without needing much attention.