Antonio Vivaldi's desperate final year was spent far from home, trying to establish himself in Vienna. He was banned from his artistic stronghold in Ferrara because word was out that this ordained priest had a longstanding relationship with his leading soprano. In his native Venice — scene of many feast-and-famine episodes — Vivaldi had long been considered washed up. Financially strapped, he sold bundles of concertos in Vienna, but his ambitions, there and most everywhere in his professional life, lay in opera. After those hopes died in 1741, so did he. Though he is known among both mainstream and crossover...