Church went even further with "Our Banner in the Sky."

Painted in 1861 and one of only two works of overt propaganda that Church would make, “Banner” wasn't a critical success; it lacked the ambiguity and complexity of his more haunting pieces. But it was hugely popular, inspiring poems, songs, and lithographs, hung throughout the Union.

Chromolithograph, published by Groupil & Co., 1861, oil over chromolithograph, after Frederic Edwin Church, Our Banner in the Sky, April-May 1861, 7 9/16 x 11 3/8 in., OL.1986.29, Collection Olana State Historic Site, NYS OPRHP

The writer Theodore Winthrop was one of Church's closest friends. Two months into the Civil War, he became the first Union officer killed in battle. Johnson writes that by the summer of 1861, sunsets meant three things to Church: "nation, war, and Winthrop."

"Brushstrokes were thick and rough," Johnson writes. "A cloud bank the color of fresh blood lay along the horizon; the rest of the sky was the rusty red of dried blood. It was the angriest sunset he had ever painted."

Ten years before his death on June 10, 1861, Winthrop wrote prophetically:

Let me not waste in skirmishes my power,—

In petty struggles,—rather in the hour

Of deadly conflict may I nobly die!

In my first battle perish gloriously!

Frederic Church, “Sunset over the Hudson Valley, Hudson, New York,” July 1861, brush and oil on canvas backed with paper, 79/16 × 1115/16 in., Cooper Hewitt, Smithsonian Design Museum, Gift of Louis P. Church, 1917-4-791

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