On Feb. 4, 1794, the legislators of France’s revolutionary government abolished slavery in all its colonies. Their decree made France the first country to end an institution that had been fundamental to the enterprise of European colonization for three centuries. Historian Jeremy Popkin tells how pressure from the enslaved populations of France’s colonies met the idealistic principles of the French revolutionaries.

Long before modern art found its home in museums, it thrived in salons, collections, and networks cultivated by women. From gatherings in Europe to avant-garde circles in early 20th-century New York, these women nurtured artists, championed emerging talent, and shaped the tastes that defined modern culture. In a 3-session series, art historian Jennie Hirsh highlights the salonnières and patrons who forged spaces where innovation flourished. This session focuses on Gertrude Stein, Helene Kröller-Müller, and Margherita Sarfatti. (World Art History Certificate elective, 1/2 credit)

The reasons behind why the daytime sky is blue, what causes a rainbow, and the creation of a halo around the moon or sun all involve how sunlight interacts with the Earth’s atmosphere. J. Kelly Beatty, senior editor at Sky & Telescope magazine, introduces you to the score of atmospheric phenomena that you can see in a daytime sky, from sun pillars at dawn to the Belt of Venus at dusk.

Historian Daniel Schlafly and limnologist Michael Meyer explore the intertwined natural and human histories of Lake Baikal, from its geological origins at least 25 million years ago to the present. The lake is both the deepest and the most voluminous in the world. More than a thousand plant and animal species live here and nowhere else. Its human history has been touched by Cossacks and the Trans-Siberian Railroad, and its waters hold profound spiritual meaning for the indigenous Buryat Mongols.

Designing a garden, whether small or large, means considering many factors. Ecologist Shaun McCoshum offers innovative conservation and ecological ideas to create a garden in a way that he says can help restore broken natural processes and build resilient ecosystems. While native plants are essential, McCoshum believes it’s also important to understand the needs of animals, their habitats, and how natural systems work together.

In an era marked by concerns over tariffs, political polarization, and shifting global alliances, questions about the durability of the U.S. dollar’s international dominance are becoming increasingly urgent. Economist Barry Eichengreen traces the evolution of cross-border money from the earliest coinage of the 7th century B.C.E. to modern cryptocurrencies and emerging central bank digital currencies. Eichengreen examines patterns in the life cycles of international currencies over the past 2,500 years, offering valuable lessons about how currencies rise—and why they fall.

Since ancient times, the Ganges has been embodied as the goddess Ganga, and her reach stretches well beyond the riverbanks. Art historian Robert DeCaroli traces the Ganges from its origins in the Himalayas to the Bay of Bengal, exploring historic and sacred locations along the way. He also examines the art and architecture used to enhance and replicate access to Ganga’s sacred waters. (World Art History Certificate elective, 1/2 credit)

The U Street NW neighborhood has long been a vibrant corridor for the rich social, civic, and cultural life of Washington's African American community. Join local guide Lynn O’Connell on a walking tour that focuses on the history of the neighborhood. Sites visited include the African American Civil War Memorial, the legendary Howard Theatre, and the locations of one-of-a-kind murals featuring such history makers as Duke Ellington and go-go legend Chuck Brown.