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12th-century illustration of the use of Greek fire

The first Arab siege of Constantinople in 674–678 was a major conflict of the Arab–Byzantine wars, and the first culmination of the Umayyad Caliphate's expansionist strategy towards the Byzantine Empire. In 672–673 Arab fleets secured bases along the coasts of Asia Minor, and set up a loose blockade around Constantinople. They used the peninsula of Cyzicus near the city as a base to spend the winter, and returned every spring to launch attacks against the city's fortifications. Finally the Byzantines managed to destroy the Arab navy using a new invention, the liquid incendiary substance known as Greek fire (pictured). The Byzantines also defeated the Arab land army in Asia Minor, forcing them to lift the siege. A peace treaty was signed, and following the outbreak of another Muslim civil war, the Byzantines experienced a brief period of ascendancy. The siege was the first major Arab defeat in 50 years of expansion. Tales of a large-scale siege of Constantinople even reached China. (Full article...)

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On this day

November 20: Transgender Day of Remembrance

Graffiti from the occupation of Alcatraz

284 – Diocletian became Roman emperor, eventually establishing reforms that ended the Crisis of the Third Century.
1739 – War of Jenkins' Ear: A British naval force arrived at the settlement of Portobello in the Spanish Main, capturing it the next day.
1969 – A group of Native American activists began a 19-month occupation (graffiti pictured) of Alcatraz Island in San Francisco Bay.
1979 – Armed insurgents attacked and took over the Masjid al-Haram in Mecca, declaring that one of their leaders was the Mahdi, the prophesied redeemer of Islam.
1994 – In accordance with the Lusaka Protocol, the Angolan government signed a ceasefire with UNITA rebels in a failed attempt to end the Angolan Civil War.

Carl Axel Arrhenius (d. 1824)
Benoit Mandelbrot (b. 1924)
Meredith Whitney (b. 1969)
Ancel Keys (d. 2004)

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Today's featured picture

Machado de Assis (1839–1908) was a Brazilian novelist, poet, playwright and short-story writer, widely regarded as the greatest writer of Brazilian literature. In 1897, he founded and became the first president of the Brazilian Academy of Letters. He was multilingual, having taught himself French, English, German and Greek later in life. Machado's work shaped the realist movement in Brazil and the birth of the Brazilian republic made Machado become more critical and an observer of the Brazilian society of his time. Generally considered to be Machado's greatest works are Dom Casmurro (1899), Memórias Póstumas de Brás Cubas (Posthumous Memoirs of Brás Cubas, also translated as Epitaph of a Small Winner) and Quincas Borba (also known in English as Philosopher or Dog?). In 1893, he published "A Missa do Galo" ("Midnight Mass"), often considered to be the greatest short story in Brazilian literature. This photograph of Machado was taken by the Brazilian photographer Marc Ferrez in 1890.

Photograph credit: Marc Ferrez; restored by Adam Cuerden

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