This is a timeline of the history of organized crime.

• 1860-1869: affirmation of the Sicilian mafia.
• 1870s: 1870 - 1871 - 1872 - 1873 - 1874 - 1875 - 1876 - 1877 - 1878 - 1879
• 1880s: 1880 - 1881 - 1882 - 1883 - 1884 - 1885 - 1886 - 1887 - 1888 - 1889
• 1890s: 1890 - 1891 - 1892 - 1893 - 1894 - 1895 - 1896 - 1897 - 1898 - 1899
• 1900s: 1900 - 1901 - 1902 - 1903 - 1904 - 1905 - 1906 - 1907 - 1908 - 1909
• 1910s: 1910 - 1911 - 1912 - 1913 - 1914 - 1915 - 1916 - 1917 - 1918 - 1919
• 1920s: 1920 - 1921 - 1922 - 1923 - 1924 - 1925 - 1926 - 1927 - 1928 - 1929
• 1930s: 1930 - 1931 - 1932 - 1933 - 1934 - 1935 - 1936 - 1937 - 1938 - 1939
• 1940s: 1940 - 1941 - 1942 - 1943 - 1944 - 1945 - 1946 - 1947 - 1948 - 1949
• 1950s: 1950 - 1951 - 1952 - 1953 - 1954 - 1955 - 1956 - 1957 - 1958 - 1959
• 1960s: 1960 - 1961 - 1962 - 1963 - 1964 - 1965 - 1966 - 1967 - 1968 - 1969
• 1970s: 1970 - 1971 - 1972 - 1973 - 1974 - 1975 - 1976 - 1977 - 1978 - 1979
• 1980s: 1980 - 1981 - 1982 - 1983 - 1984 - 1985 - 1986 - 1987 - 1988 - 1989
• 1990s: 1990 - 1991 - 1992 - 1993 - 1994 - 1995 - 1996 - 1997 - 1998 - 1999
• 2000s: 2000 - 2001 - 2002 - 2003 - 2004 - 2005 - 2006 - 2007 - 2008 - 2009
• 2010s: 2010 - 2011 - 2012 - 2013 - 2014 - 2015 - 2016 - 2017 - 2018 - 2019
• 2020s: 2020 - 2021 - 2022 - 2023 - 2024 - 2025 - 2026 - 2027 - 2028 - 2029

• Timeline of organized crime in Chicago

• Sources included are Carl Sifakis's The Mafia Encyclopedia, Herbert Asbury's The Gangs of New York and others. Online references also include Thomas P. Hunt's Mafia Chronology, John Dickie's Cosa Nostra history and The Chronological History of La Cosa Nostra in the United States: January 1920 - August 1987 compiled by the United States Department of Justice Criminal Division's Organized Crime Intelligence and Analysis Unit.