Cryptologic Dates in History Calendar

"On This Date in Cryptologic History" Calendar

Learn about a wide variety of historical events related to cryptology, computers, math, cybersecurity, Intelligence, and more.

December 2026

This Month

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29	Nov 30	Dec 1	2	3	4	5
		1887: U.S. Navy began using "The U.S. Navy Secret Code"
		1932: Polish Cipher Bureau Success!
		1950: ATLAS became operational.

6	7	8	9	10	11	12
	Pearl Harbor Day		1992: Premiere of William Gibson's "Agrippa"	1815: Birth of Ms. Ada Lovelace, the world's first computer programmer	1941: Germany and Italy Declared War on the U.S.
			1906: Birth of Grace Hopper - computer pioneer and U.S. Navy Rear Admiral

13	14	15	16	17	18	19
	1977: Filing for RSA Patent	1562: Death of Johannes Trithemius	1972: NSOC Inaugurated	OTD in 1993: National Cryptologic Museum Opened to the Public	2013: Death of Dr. Lowell K. "Jim" Frazer	1801: Patterson's "Perfect Cipher" Letter sent to Thomas Jefferson
	1958: First NSA Holiday Party.

20	21	22	23	24	25	26
1881: First telephone ciphony device invented by James Harris Rodgers.		1961: SP4 James Davis - first American cryptologist killed in Vietnam.	1968: "Pueblo" crew released by North Korea.	1928: Friedman's Coded Holiday Gram	Holiday Season Memories - NSA Building Messages
20 Dec 1969: Anniversary of the Capture of North Vietnamese Notebooks		2001: Shoe-bomber Richard Reid arrested.
1946: Meredith Gardner broke into KGB message re: Manhattan Project.

27	28	29	30	Dec 31	Jan 1	2
1948: Stone Board report on centralizing U.S. cryptologic organizations was issued.	1951: Brownell Committee established - led to creation of NSA.			1921: William Friedman at Office of the Chief Signal Officer

Pearl Harbor Day

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1815: Birth of Ms. Ada Lovelace, the world's first computer programmer

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1941: Germany and Italy Declared War on the U.S.

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1562: Death of Johannes Trithemius

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1972: NSOC Inaugurated

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OTD in 1993: National Cryptologic Museum Opened to the Public

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2013: Death of Dr. Lowell K. "Jim" Frazer

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1801: Patterson's "Perfect Cipher" Letter sent to Thomas Jefferson

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1968: "Pueblo" crew released by North Korea.

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1928: Friedman's Coded Holiday Gram

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Holiday Season Memories - NSA Building Messages

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1948: Stone Board report on centralizing U.S. cryptologic organizations was issued.

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1951: Brownell Committee established - led to creation of NSA.

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1921: William Friedman at Office of the Chief Signal Officer

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