John Napier is the first contemporary biography to take an in-depth look at the multiple facets of Napier's story: his privileged position as the seventh Laird of Merchiston and the son of influential Scottish landowners; his reputation as a magician who dabbled in alchemy; his interest in agriculture; his involvement with a notorious outlaw; his staunch anti-Catholic beliefs; his interactions with such peers as Henry Briggs, Johannes Kepler, and Tycho Brahe; and, most notably, his estimable mathematical legacy. John Napier assesses one man's life and the lasting influence of his advancements on the mathematical sciences and beyond.