Architect Arnolfo di Cambio oversaw the start of construction on Florence's new cathedral, intended to surpass the great churches of rival Tuscan cities Siena and Pisa. The building's crowning achievement, Filippo Brunelleschi's massive octagonal dome, would not be finished until 1436, making the cathedral a multigenerational civic monument.

Florida's admission to the Union came after Spain ceded the territory to the United States in 1821 and after two brutal wars against the Seminole nation, who resisted removal from their ancestral lands. Statehood cemented Florida's entry as a slave state, part of the delicate sectional balance in Congress preceding the Civil War.

Born to a family steeped in speech and elocution—his father developed a system of phonetic symbols and his mother was deaf—Bell grew up fascinated by sound and hearing. That upbringing shaped his life's work, from teaching deaf students to inventing the telephone, which he patented at age 29 and demonstrated with the famous words, 'Mr. Watson, come here, I want to see you.'

Originally built as a fort to defend San Francisco Bay during the Gold Rush era, Alcatraz Island's isolation and treacherous currents made it an ideal site for confining military prisoners, including Confederate sympathizers and Native American captives. The island's reputation as an inescapable prison would culminate decades later in its transformation into a federal penitentiary.

Signed at the end of the Russo-Turkish War of 1877–78, the treaty forced the Ottoman Empire to recognize a vastly enlarged, autonomous Bulgarian state under Russian influence. Alarmed by Russia's expanded reach into the Balkans, Britain and Austria-Hungary demanded revisions, leading to the Congress of Berlin months later, which shrank Bulgaria's borders considerably.

The treaty, negotiated just days after Panama declared independence from Colombia with covert American backing, gave the United States rights 'in perpetuity' over a 10-mile-wide Canal Zone. The arrangement enabled construction of the Panama Canal, completed in 1914, but generated decades of Panamanian resentment over sovereignty that culminated in the treaties of 1977 returning the canal to Panama.

Organized by suffragist Alice Paul, the parade drew thousands of spectators, many of them hostile, and descended into chaos as crowds jeered and jostled marchers while police largely failed to intervene. Cavalry troops eventually restored order, and the resulting public outrage over the treatment of the marchers generated sympathetic press coverage that boosted the suffrage movement's momentum toward the 19th Amendment.

Fulfilling a campaign promise made in an impromptu late-night speech at the University of Michigan, Kennedy formalized the Peace Corps by executive order, appointing his brother-in-law Sargent Shriver as its first director. The agency aimed to promote mutual understanding between Americans and people of developing nations through grassroots service rather than military or purely economic aid.

Recorded largely at Abbey Road Studios, the album was a meditation on the pressures that drive people toward madness, inspired partly by former bandmate Syd Barrett's mental breakdown. Its innovative use of studio effects, spoken-word interviews, and seamless track transitions made it a landmark of progressive rock and one of the best-selling albums in history, with estimated sales exceeding 45 million copies.