He was born on July 5, 1924 in Holzminden, Germany. Jannasch served with coastal forces in the German navy in World War Two. After the war he sailed in merchant ships under Finnish and German flags, most notably the four-masted barque Passat during the last grain race. On this, her last commercial voyage, he served as ship's carpenter. When she was refitted as a training ship he re-joined as bosun. He married Barbara Dierig in 1952 and the couple emigrated to Halifax, Nova Scotia. Jannasch became the first director of the Maritime Museum of Canada in 1959 and oversaw its growth and many plans before it finally moved to a large waterfront location in 1981, and became the Maritime Museum of the Atlantic.
He retired in 1985 but continued to go to sea and contribute to marine scholarship in many ways. He was a founder and charter member of the Canadian Nautical Research Society. His deep knowledge and tireless contribution to many heritage organizations and made him "an icon of the maritime history fraternity in Canada and aboard." He was invested into the Order of Canada in 1991 in recognition of his scholarly and public contributions.
Jannasch died at his home in Seabright, Nova Scotia on November 9, 2001. He is commemorated by a replica sailing sloop named Windekilde and the Niels Jannasch Library at the Maritime Museum of the Atlantic.
- Parrott, Daniel S. (2004). Tall Ships Down: The Last Voyages of the Pamir, Albatross, Marques, Pride of Baltimore, and Maria Asumpta (revised ed.). McGraw Hill Professional. pp. 32, 45. ISBN 9780071435451. Retrieved 6 April 2019.
- Walters, Ed (29 April 1964). "This Sailor Enjoys The Contentment He's Always Sought". The Brandon Sun. Brandon, Manitoba. CP. p. 21. Retrieved 26 March 2019.
- "Former Naval Officer". Calgary Herald. Calgary, Alberta. 25 May 1964. p. 15. Retrieved 6 April 2019.
- "Long Wait". The Ottawa Citizen. Ottawa, Ontario. 19 January 1982. p. 21. Retrieved 6 April 2019.
- Gough, Barry: "Niels Jannasch", Argonauta, newsletter of the Canadian Nautical Research Society, Oct 2001, page 4. Retrieved 2019-03-26.
- "Order of Canada Recipients database", The Governor General of Canada
- Sloop Windekilda Maritime Museum of the Atlantic. Retrieved 2019-03-26.
- "Niels Jannasch Library", Maritime Museum of the Atlantic. Retrieved 2019-03-26.
Obituaries: Toronto Globe and Mail and Halifax Chronicle Herald November 12, 2001
- Windekilde replica
- Obituary Argonauta, newsletter of the Canadian Nautical Research Society, Oct 2001, p.4-5