It’s hard not to leave “Franz Marc and August Macke: 1909-1914,” an alternately thrilling and dizzying exhibition on the artistic friendship of two important German painters, saddened by the tragic end of both men’s careers.

On a trip to a gallery in 1910, Macke, who was impressed by Marc’s confident lithographs of animals, asked for the artist’s address and immediately went to visit. The two men subsequently traveled and showed together. With the Russian-born Wassily Kandinsky, they also helped found the Blue Rider, a loose collective of Munich painters whose impatience with the stuffiness of realistic work helped open the path to German Expressionism, with its bold, tactical exaggeration, and, later, to abstraction.

Established in 1911, the group took its name from an almanac of essays and reproductions edited by Marc and Kandinsky and paid for by the wealthy collector Bernhard Koehler, the uncle of Macke’s wife. But World War I brought this all to an end: Macke was killed at 27 in combat in 1914; Marc died on the battlefield just after his 36th birthday, in 1916.