When did the term "evangelical" first start being used? The term "evangelical" is used to describe a particular set of Christian beliefs, and is generally considered orthogonal to denominations - you could get, for example, evangelical Anglicans and non-evangelical Anglicans.  I've also heard the term used (or at least implied) of Christians from past centuries who ascribe to those same beliefs. For example, I'm not sure if the likes of Spurgeon or Wesley would have called themselves "Evangelical", but they are often spoken of in those terms.

When did the particular set of beliefs currently referred to as "evangelicalism" gain that name, and what was the historic context that required the distinction?
Having done some more research, the Wikipedia article on Evangelicalism and this overview by the Gospel Coalition suggest the following timeline for the term coming into use:

1500s: Protestant reforms use the word "evangelical" in its literal meaning: the greek word meaning "gospel". This was to emphasise their message based on what they saw in the Bible.

1600s: In the wake of the reformation, a number of different movement appeared across Europe, such as Pietism and Calvinism, each emphasising different aspects of the reformation.

1700s: British and American reformers start to combine elements from all these different movements into movement, and take on the word "evangelical" that was used by the original reformers. In part, this movement was motivated by a renewed assurance in their faith, and in part a natural outcome of the changes happening in wider society.

I suspect this brushes over much of the historical nuance, but appears to serve as a general overview.