- Sep 1 Debbie Boone & Gabriel Ferrer wed in LA
- Sep 1 LA Court orders Clayton Moore to stop wearing Lone Ranger mask
- Sep 1 Pioneer 11 makes 1st fly-by of Saturn, discovers new moon, rings
- Sep 2 "I Remember Mama" closes at Majestic Theater NYC after 108 performances
- Sep 2 US Men's Amateur Golf Championship, Canterbury GC: Mark O'Meara wins 8 & 7 over John Cook
- Sep 3 Hurricane David, a strong Atlantic storm kills over 1,000
- Sep 3 Iran army conquers Mahabad
Event of Interest
Sep 3 Jerry Lewis' 14th Muscular Dystrophy telethon raises $30,000,000

Jerry Lewis
- Sep 4 Sunil Gavaskar scores his third double century in Test cricket (221) to guide India to a famous draw against England in the 4th Test at The Oval
- Sep 4 India need 438 to win v England, game ends at 8-429
- Sep 4 Iran army conquers Baneh
- Sep 5 Oakland A's pitcher Matt Keough beats Milwaukee Brewers, 6-1 for first win after 14 straight losses, ended 1978 with 18 defeats (1 shy of the MLB record 19)
- Sep 5 Canada puts its first gold bullion coin on sale
Event of Interest
Sep 5 Earl of Mountbatten's Ceremonial Funeral held in Westminster Abbey

Lord Mountbatten
- Sep 5 Iranian army occupies Piranshahr
US Men's Tennis Open
Sep 5 American Roscoe Tanner fires 11 aces, breaks the net with his bullet serve and upsets top-seed Björn Borg 6-2, 4-6, 6-2, 7-6 in the US Open Tennis quarterfinals

Roscoe Tanner

Björn Borg
- Sep 6 "Peter Pan" opens at Lunt-Fontanne Theater NYC for 578 performances
- Sep 7 5 day MUSE concert against nuclear energy opens at Madison Square Garden, New York
- Sep 7 The Entertainment and Sports Programming Network (ESPN) makes its debut.
- Sep 8 Cheryl Prewitt (Miss), 22, crowned 52nd Miss America 1980
- Sep 8 US performs nuclear test at Nevada Test Site
US Open Women's Tennis
Sep 8 US Open Women's Tennis: Tracy Austin becomes youngest US champion (16 years, 9 months); beats Chris Evert 6-4, 6-3

Chris Evert
US Men's Tennis Open
Sep 9 US Open Men's Tennis: John McEnroe wins first Grand Slam title; beats fellow American Vitas Gerulaitis 7-5, 6-3, 6-3

John McEnroe
- Sep 9 South African Ferrari driver Jody Scheckter wins the Italian Grand Prix at Monza to clinch his first Formula 1 World Drivers Championship; first RSA champion
- Sep 10 3 Puerto Rican nationalists who attempted to kill Truman are freed
- Sep 12 Hurricane Frederick hits Mobile Alabama; 5 die & $23 million damage
- Sep 12 Indiana Pacers cut Ann Meyers, 1st woman on an NBA club
Baseball Record
Sep 12 Carl Yastrzemski gets his 3,000th hit off NY Yankee Jim Beattie

Carl Yastrzemski
- Sep 12 Indonesia is hit with an earthquake that measures 8.1 on the Richter scale.
- Sep 13 China performs nuclear test at Lop Nor, PRC
- Sep 13 South Africa grants Venda independence (Not recognized out of South Africa)
- Sep 14 USSR performs nuclear test at Eastern Kazakh/Semipalitinsk USSR
- Sep 14 Theodore Coombs completes 5,193 mile roller skate from LA to NYC & back to Yates Center, Ks
- Sep 14 The film "Quadrophenia", loosely based on The Who's 1973 rock opera of the same name is released.
- Sep 15 Red Sox Bob Watson is 1st to hit for cycle in AL & NL (Astros)
- Sep 15 USSR performs nuclear test at Eastern Kazakh/Semipalitinsk USSR
- Sep 15 4th Toronto International Film Festival: "Best Boy" directed by Ira Wohl wins the People's Choice Award
- Sep 16 Ryder Cup Golf, The Greenbrier: US wins, 17-11; new Team Europe replaces Great Britain & Ireland as official opposition to the United States
- Sep 16 Catfish Hunter Day at Yankee Stadium
- Sep 16 Coup in Afghanistan under Hafizullah Amin
- Sep 16 KC's Willie Wilson hits 5th inside-the-park HR (most since 1925)
- Sep 16 USSR performs nuclear test
- Sep 16 The families of Peter Strelzyk and Gunter Wetzel arrive in West Germany from Communist East Germany in a hot air balloon
- Sep 17 Pietro Mennea runs world record 200 m (19.72")
Baseball Record
Sep 17 Royals' George Brett is 6th to have 20 doubles/triples/HRs in a season

George Brett
Dictator Bokassa I
Sep 20 Coup in Central African Republic as David Dacko overthrows Emperor Bokassa I
Learn More- Sep 20 Jose E dod Santos becomes president of Angola
- Sep 20 NASA launches HEAO 3
- Sep 20 Lee Iacocca is elected president of the Chrysler Corporation
- Sep 20 The Punjab wing of the Unity Centre of Communist Revolutionaries of India (Marxist-Leninist) formally splits and constitutes a parallel UCCRI(ML).
- Sep 20 Assassination of French left-wing militant Pierre Goldman.
- Sep 21 Two RAF Hawker Siddeley Harrier jump-jets from RAF Wittering collide over Wisbech in Cambridgeshire. Both pilots eject safely, but three people killed and several injured when one of the aircraft destroys 3 dwellings
Event of Interest
Sep 21 Stephen Jay Gould and Richard Lewontin publish influential paper (cited more than 4,000 times) "The Spandrels of San Marco and the panglossian paradigm", introducing idea of "spandrels" into evolutionary biology

Stephen Jay Gould
Event of Interest
Sep 23 Jane Fonda & 200,000 attend anti-nuke rally in Battery Park, NYC

Jane Fonda
- Sep 24 Russian ice skaters Protopopov & Beloussova ask for asylum in Switzerland
- Sep 24 USSR performs nuclear test at Novaya Zemlya USSR
- Sep 25 "Evita" opens at Broadway Theater NYC for 1568 performances
- Sep 25 California Angels win their 1st NL West pennant
- Sep 26 1984 summer LA Olympic coverage sold to ABC for $225 million
- Sep 26 US performs nuclear test at Nevada Test Site
- Sep 27 US Congress' final approval to create Department of Education
Event of Interest
Sep 27 Elton John, sick with flu, collapses in the Hollywood Universal Amphitheater

Elton John
- Sep 27 USSR performs nuclear test at Eastern Kazakh/Semipalitinsk USSR
Boxing Title Fight
Sep 28 Larry Holmes TKOs Earnie Shavers in 11 for heavyweight boxing title

Larry Holmes
Event of Interest
Sep 29 "Different Worlds" by Maureen McGovern peaks at #18

Maureen McGovern
- Sep 29 "Driver's Seat" by Sniff 'n' the Tears peaks at #15
- Sep 29 "Girls Talk" by Dave Edmunds peaks at #65
- Sep 29 "Lonesome Loser" by Little River Band peaks at #6
- Sep 29 "Message In A Bottle" by Police peaks at #1 in UK
- Sep 29 "What Cha Gonna Do With My Lovin'" by Stephanie Mills peaks at #22
- Sep 29 Astros' J R Richard strikes out NL season righty record of 313
- Sep 29 Gold hits record $400.20 an ounce in Hong Kong
- Sep 29 John Huston's "Wine Blood" premieres at NY Film Festival
- Sep 29 LA Dodger Manny Mota hits record 146th pinch hit
Papal Visit
Sep 29 Pope John Paul II becomes 1st pope to visit Ireland

John Paul II
- Sep 30 Milwaukee Brewers lose 5-0 ending 213 straight games without a shutout