Lybeck was commissioned as an officer in the
Swedish Navy with the rank of
underlöjtnant in 1892. He was promoted to sub-lieutenant in 1895, and undertook language studies in Russia from 1895 to 1897, after which he served as Russian language teacher in the
Naval Staff before attending the
Royal Swedish Army Staff College from 1898 to 1900. He then served in the
Fleet Staff for four years, and advancing to the rank of lieutenant in 1901. In 1904, he was sent to East Asia to observe the
Russo-Japanese War. During this time, Lybeck was also a member of the Military Pay Experts (
Militära avlöningssakkunniga) from 1919 to 1922 and a member of the Defense Audit (
Försvarsrevisionen) from 1922 to 1923. He then served as commanding officer of the 4th Coastal Defence Ship Division (
Fjärde pansarbåtsdivisionen) from 1922 to 1923 and as Inspector of the Submarine Force (
Inspektör för ubåtsvapnet) in 1924. Lybeck was promoted to rear admiral in 1925 and in 1926 he was appointed Commander-in-Chief of the
Coastal Fleet. In 1927, he was appointed
Chief of the Naval Staff, a position Lybeck had for the next nine years. He was chairman of the Naval Teaching Commission (
marinundervisningskommissionen) in 1928, and of the board of the
Nautical Chart Department from 1929 to 1936. Lybeck was also chairman of the board of the
Royal Swedish Yacht Club (KSSS) from 1936 to 1946 and of the
Swedish Sailing Federation from 1937. He served as a member of the Committee on Stockholm's Naval Station from 1929 to 1930. ==Personal life==