Stanisław Leopold Janikowski was born in Piotrków, southern Poland, son of Leopold and Zofia (née Krajcewicz). He spent most of his married life in Rome, Italy, until returning to Poland in 1965. On September 23, 1965, he died aged 77 in his parents' home in Zielonka, near Warsaw and is buried in Warsaw.
From his school years Stanisław was involved in the underground fighting against the Tsar. His code name in these secret activities was Wampir (English: Vampire). He joined the Revolution with the school strike of 1905 against Russification. He belonged to the Polskie Drużyny Strzeleckie (English: Polish Rifle Squads, a Polish pro-independence paramilitary organization tolerated by the Austrian government in Kraków)  and the Sokół (Polish: Polskie Towarzystwo Gimnastyczne "Sokół", English: Polish Gymnastic Society "Falcon"). Poor Health and the outbreak of World War I meant that he was unable to complete his studies at the Jagiellonian University. Since he could not be accepted by the regular army, during the World War, he was active in the secret Wolnej Szkole Wojskowej (English: Free Cadet School) in Warsaw. From 1914 he was a member of the clandestine Central Committee of ‘ZET’ the Association of the Polish Youth (Polish: Związek Młodzieży Polskiej)  and from 1915 in the secret Polska Organizacja Wojskowa (POW - English: Polish Military Organization). From 1918, with former members of ZET who also could no longer be considered to be “youth”, he was a committee member of Związku Patriotycznym (English: Patriotic League)  and then with the Związek Naprawy Rzeczpospolitej (English: Union for Improvement of the Republic).
S.L. Janikowski joined the Polish diplomatic service on November 15, 1918. In 1920 he was a member of the Polish delegation to Minsk. In 1921 he took part, as a member of the Polish delegation, in the Peace of Riga negotiations. He then stayed on in Lithuania, leading delicate negotiations to create a majority in the Sejm in Vilnius, supporting policies of the speaker Józef Piłsudski.
After returning to Warsaw he worked for a short time in the Eastern Department of the Ministry of Foreign Affairs of the Republic of Poland. In 1927 he took office as Counsellor in the Embassy of the Second Polish Republic to the Holy See.
World War II
On the outbreak of World War II and the internment of the Polish authorities, Janikowski was designated to prime position by the nominated President of the Second Polish Republic General Bolesław Wieniawa-Długoszowski.
From 1944 until July 7, 1945 he acted as director  of the Embassy of the Second Polish Republic to the Quirinale  with the title of Minister Plenipotentiary. He continued to co-operate with Kazimierz Papée, though he was not formally mentioned in the Annuario Pontificio.
From January to May 1954 he stayed in London, where he held the post of Minister of Foreign Affairs in the Polish Government in Exile  of Jerzy Hryniewski. On his return to Rome, Janikowski took up radio broadcasting. In 1965 he returned to Poland with his wife and settled in Zielonka, (in the road named after his father, the explorer Leopold Janikowski), near Warsaw, where he died a few months later on September 23, 1965. He was buried on September 27, 1965 - Melchior Wańkowicz gave a funeral oration - in the family grave in Powązki Cemetery in Warsaw.
Stanisław Janikowski was the only child of Leopold (1855 – December 8, 1942) and Zofia Krajcewicz (November 21, 1867 – April 26, 1963). Leopold Janikowski was a Meteorologist by training, becoming an Ethnographer and travelling to the Camerouns in West Africa on two voyages in the 1880s.
Stanisław met his future wife Halina Prewysz-Kwinto during his stay in Wilno, and they later married in 1925. She was born on September 23, 1898 at Lipniszki, in Lithuania. They had three children. Their daughter was Hanna Maria, born July 21, 1926 in Warsaw, who married Edward Szczepanik in Rome on June 29, 1946. She had 4 children and lived in London, Hong Kong, Rome and latterly Lewes, East Sussex, England. She died on December 23, 1995.
Their first son Stanisław Maria was born in Rome on November 28, 1927. After the war he settled in England, where he still lives, in Felixstowe, and married Bridget Harkin, from Ireland, having a daughter.
The last son, Wojciech Ignacjy Maria, was born July 31, 1935 in Wilno, Lithuania. He has spent all his life in Rome, Italy, with two sons.
Halina died in Zielonka, Warsaw, on December 18, 1981, 16 years after her husband Stanisław Leopold Janikowski.
- "By February 1905, the protest movement had spread to Polish educational institutions, where the major cause of discontent was Russification… Pupils at high schools and even at some elementary schools, stopped attending class and joined street demonstrations." Ascher, Abraham. The Revolution of 1905: Russia in Disarray. Stanford University Press, 1994, ISBN 0-8047-2327-3, Google Print, p.158
- Sienkiewicz, Witold. Mały słownik historii Polski. Warszawa: Wiedza Powszechna, 1991. ISBN 83-214-0648-3 Google Print, Page 162
- cf Archiwum Pułkownika Konrada Libickiego in The Jozef Pilsudski Institute In New York
- Encyklopedia Internautica (automatic translation)
- Tomasiewicz, Jarosław. Niepodległościowe tradycje socjalistów w II RP Lewica.pl 2005-09-19 (automatic translation)
- Waingertner, Przemysław. "Naprawa": (1926-1939) : z dziejów obozu pomajowego. Warszawa: Wydawnictwo Naukowe "Semper", 1999. ISBN 83-86951-58-3 Google Print pg. 18-19
- "Upon the arrival of the delegation in Minsk, the Belarusian capital, the Polish delegates were treated as representatives of a defeated enemy. Not only were they isolated and subjected to various forms of psychological pressure. It was announced that the Polish delegation composed exclusively of spies and that it was endeavouring to carry on spying activities." Ajnenkiel. Andrzej The Treaty of Riga - Its Origins and Significance
- Dąbrowski, Stanisław. The Peace Treaty of Riga, 1921. Kent, Ohio: s.n., 1968. Google Print, Page 143
- Polish Wikipedia: Polscy ambasadorzy Stolica Apostolska
- "In January 1945, the Polish government In London appointed Stanisław Janikowski to Rome as its Charge d'Affaires ad interim to the Italian government. Italy did not do likewise". G.Petracchi, Italy and Eastern Europe, 1943-1948, Pg. 127 in The Failure of Peace in Europe, 1943-48 Edited by: Antonio Varsori and Elena Calandri (Palgrave Macmillan 2002) ISBN 978-0-333-72338-8. Petracchi refers to V. Mastny, Soviet War Aims at the Moscow and Teheran Conferences of 1943, Journal of Modem History 47 (1975): pp. 481-504
- Quirinale as the official residence of the President refers to the Italian Republic (as distinct from The Holy See)
- The Ukrainian Quarterly, Ukrainian Congress Committee of America, Ukraine History Periodicals 1944 refers to him as "Dr. Stanisław Janikowski, former Polish Ambassador in Rome" Google Print Pg 84
- The United Kingdom withdrew recognition on July 6, 1945
- maps.google.com Leopolda Janikowskiego, Zielonka, Warsaw, Poland
Polish: Czy wiesz kto to jest? ["Who's Who"] (Warsaw 1938)
Polish: publication by the Association of Poles in Italy (Italian: Associazione dei Polacchi in Italia / Polish: Związek Polaków we Włoszech) of a collection of articles covering "Political, public and cultural activity of Poles in Rome in the 20th century"
Pro publico bono : Polityczna, społeczna i kulturalna działalność Polaków w Rzymie w XX wieku
red. Ewa Prządka. - Rzym : Fundacja Rzymska im. J. S. Umiastowskiej, 2006. - 478 s., 77 fot. (Polonica włoskie ; 5. Świadectwa 4)