| | Event type
100 metres Backstroke, Men
| Date | 4 – 6 August 1948 |
|---|---|
| Status | Olympic |
| Location | Wembley Arena, Wembley, London |
| Participants | 39 from 24 countries |
Earlier in the year Allan Stack had broken Adolph Kiefer’s twelve year old world record for this event and the stylish American was considered a strong favourite to follow Kiefer as Olympic champion. Stack was fastest in both heat and semi-final but had a nasty surprise as he lined up for the start of the final. As he waited in the water he attempted to tighten his swimming trunks and felt the cord break in his hands and his trunks begin to slip off. Fortunately the starter allowed him to leave the pool and replace his trunks and avoid what could have been an embarrassing situation for him. The final turned out to be much closer than had been anticipated with Stack’s fellow American, Robert Cowell, pressing him throughout and even leading at one stage. The difference between gold medal winner Stack and Cowell in silver was just a tenth of a second.
| Pos | Swimmer | NOC | R1 | SF | Final | |||
|---|---|---|---|---|---|---|---|---|
| 1 | Allen Stack |  USA | 1:06.6 (1 h4) | 1:07.3 (1 h1) | 1:06.4 (1) | Gold | ||
| 2 | Bob Cowell | USA | 1:06.9 (1 h5) | 1:08.5 (1 h2) | 1:06.5 (2) | Silver | ||
| 3 | Georges Vallerey, Jr. |  FRA | 1:07.4 (1 h6) | 1:08.3 (2 h1) | 1:07.8 (3) | Bronze | ||
| =4 | Mario Chávez |  ARG | 1:09.7 (2 h3) | 1:09.8 (5 h1) | 1:09.0 (=4) | |||
| =4 | Clemente Mejía |  MEX | 1:09.8 (3 h3) | 1:09.6 (4 h1) | 1:09.0 (=4) | |||
| 6 | Jackie Wiid |  RSA | 1:08.5 (1 h1) | 1:09.2 (3 h2) | 1:09.1 (6) | |||
| 7 | John Brockway |  GBR | 1:09.2 (1 h3) | 1:09.1 (3 h1) | 1:09.2 (7) | |||
| 8 | Bert Kinnear | GBR | 1:09.7 (2 h4) | 1:09.2 (2 h2) | 1:09.6 (8) | |||
| 4 h2 r2/3 | Howard Patterson | USA | 1:09.3 (2 h6) | 1:09.9 (4 h2) | – | |||
| 5 h2 r2/3 | Paluca |  BRA | 1:10.5 (3 h6) | 1:10.1 (5 h2) | – | |||
| 6 h1 r2/3 | Paulo Silva | BRA | 1:10.0 (3 h4) | 1:09.8 (6 h1) | – | |||
| 6 h2 r2/3 | Lucien Zins | FRA | 1:10.9 (4 h3) | 1:11.5 (6 h2) | – | |||
| 7 h1 r2/3 | Cees Kievit |  NED | 1:10.8 (2 h1) | 1:11.3 (7 h1) | – | |||
| 7 h2 r2/3 | Ilo da Fonseca | BRA | 1:11.9 (2 h2) | 1:11.6 (7 h2) | – | |||
| 8 h1 r2/3 | Bruce Bourke |  AUS | 1:11.3 (1 h2) | 1:11.4 (8 h1) | – | |||
| 8 h2 r2/3 | René Pirolley | FRA | 1:11.4 (2 h5) | 1:12.9 (8 h2) | – | |||
| 3 h1 r1/3 | José Vegazzi | ARG | 1:13.8 (3 h1) | – | – | |||
| 3 h2 r1/3 | Jiří Kovář |  TCH | 1:12.9 (3 h2) | – | – | |||
| 3 h5 r1/3 | Donald Shanks |  BER | 1:17.1 (3 h5) | – | – | |||
| 4 h1 r1/3 | Francisco Calamita |  ESP | 1:14.2 (4 h1) | – | – | |||
| 4 h2 r1/3 | Carlos Noriega |  URU | 1:15.0 (4 h2) | – | – | |||
| 4 h4 r1/3 | Tony Summers | GBR | 1:11.2 (4 h4) | – | – | |||
| 4 h5 r1/3 | Dorri Abdel Kader |  EGY | 1:19.0 (4 h5) | – | – | |||
| 4 h6 r1/3 | Federico Neumayer | ARG | 1:11.8 (4 h6) | – | – | |||
| 5 h1 r1/3 | Eric Jubb |  CAN | 1:14.3 (5 h1) | – | – | |||
| 5 h2 r1/3 | Martin Lundén |  SWE | 1:15.6 (5 h2) | – | – | |||
| 5 h3 r1/3 | Mário Simas |  POR | 1:12.8 (5 h3) | – | – | |||
| 5 h4 r1/3 | Gyula Válent |  HUN | 1:11.8 (5 h4) | – | – | |||
| 5 h5 r1/3 | Guðmundur Ingólfsson |  ISL | 1:19.4 (5 h5) | – | – | |||
| 5 h6 r1/3 | Peter Mingie | CAN | 1:13.2 (5 h6) | – | – | |||
| 6 h1 r1/3 | Per-Olof Olsson | SWE | 1:14.6 (6 h1) | – | – | |||
| 6 h2 r1/3 | Tonatiuh Gutiérrez | MEX | 1:15.6 (6 h2) | – | – | |||
| 6 h3 r1/3 | Fritz Zwazl |  AUT | 1:13.5 (6 h3) | – | – | |||
| 6 h4 r1/3 | Manuel Guerra | ESP | 1:14.8 (6 h4) | – | – | |||
| 6 h6 r1/3 | Hans Blumer |  SUI | 1:18.5 (6 h6) | – | – | |||
| 7 h1 r1/3 | Kanti Shah |  IND | 1:19.9 (7 h1) | – | – | |||
| 7 h2 r1/3 | Jaffar Ali Shah |  PAK | 1:30.2 (7 h2) | – | – | |||
| 7 h3 r1/3 | Nikolaos Melanofeidis |  GRE | 1:22.0 (7 h3) | – | – | |||
| 7 h4 r1/3 | Prahtip Mitra | IND | 1:24.5 (7 h4) | – | – | |||
| Helmut Koppelstätter | AUT | – (DNS h5) | – | – | ||||
| László Gyöngyösi | HUN | – (DNS h5) | – | – | ||||
| Iftikhar Ahmed Shah | PAK | – (DNS h6) | – | – |
Round One (4 August 1948 — 14:00)
Top two in each heat and the next four fastest advanced to the semi-finals.
Heat One
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 6 | Jackie Wiid | RSA | 1:08.5 | |||
| 2 | 1 | Cees Kievit | NED | 1:10.8 | |||
| 3 | 5 | José Vegazzi | ARG | 1:13.8 | |||
| 4 | 3 | Francisco Calamita | ESP | 1:14.2 | |||
| 5 | 4 | Eric Jubb | CAN | 1:14.3 | |||
| 6 | 7 | Per-Olof Olsson | SWE | 1:14.6 | |||
| 7 | 2 | Kanti Shah | IND | 1:19.9 |
Heat Two
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 1 | Bruce Bourke | AUS | 1:11.3 | |||
| 2 | 3 | Ilo da Fonseca | BRA | 1:11.9 | |||
| 3 | 7 | Jiří Kovář | TCH | 1:12.9 | |||
| 4 | 2 | Carlos Noriega | URU | 1:15.0 | |||
| 5 | 5 | Martin Lundén | SWE | 1:15.6 | |||
| 6 | 6 | Tonatiuh Gutiérrez | MEX | 1:15.6 | |||
| 7 | 4 | Jaffar Ali Shah | PAK | 1:30.2 |
Heat Three
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 4 | John Brockway | GBR | 1:09.2 | |||
| 2 | 6 | Mario Chávez | ARG | 1:09.7 | |||
| 3 | 1 | Clemente Mejía | MEX | 1:09.8 | 1 | ||
| 4 | 5 | Lucien Zins | FRA | 1:10.9 | |||
| 5 | 3 | Mário Simas | POR | 1:12.8 | |||
| 6 | 2 | Fritz Zwazl | AUT | 1:13.5 | |||
| 7 | 7 | Nikolaos Melanofeidis | GRE | 1:22.0 |
Heat Four
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 6 | Allen Stack | USA | 1:06.6 | |||
| 2 | 1 | Bert Kinnear | GBR | 1:09.7 | |||
| 3 | 2 | Paulo Silva | BRA | 1:10.0 | |||
| 4 | 7 | Tony Summers | GBR | 1:11.2 | |||
| 5 | 3 | Gyula Válent | HUN | 1:11.8 | |||
| 6 | 4 | Manuel Guerra | ESP | 1:14.8 | |||
| 7 | 5 | Prahtip Mitra | IND | 1:24.5 |
Heat Five
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 7 | Bob Cowell | USA | 1:06.9 | |||
| 2 | 5 | René Pirolley | FRA | 1:11.4 | |||
| 3 | 1 | Donald Shanks | BER | 1:17.1 | |||
| 4 | 3 | Dorri Abdel Kader | EGY | 1:19.0 | |||
| 5 | 4 | Guðmundur Ingólfsson | ISL | 1:19.4 | |||
| 6 | Helmut Koppelstätter | AUT | – | ||||
| 2 | László Gyöngyösi | HUN | – |
Heat Six
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 7 | Georges Vallerey, Jr. | FRA | 1:07.4 | |||
| 2 | 3 | Howard Patterson | USA | 1:09.3 | |||
| 3 | 5 | Paluca | BRA | 1:10.5 | |||
| 4 | 4 | Federico Neumayer | ARG | 1:11.8 | |||
| 5 | 2 | Peter Mingie | CAN | 1:13.2 | |||
| 6 | 6 | Hans Blumer | SUI | 1:18.5 | |||
| 1 | Iftikhar Ahmed Shah | PAK | – |
Semi-Finals (5 August 1948 — 21:00)
Top three in each heat and the next two fastest advanced to the final.
Heat One
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 5 | Allen Stack | USA | 1:07.3 | |||
| 2 | 4 | Georges Vallerey, Jr. | FRA | 1:08.3 | |||
| 3 | 6 | John Brockway | GBR | 1:09.1 | |||
| 4 | 3 | Clemente Mejía | MEX | 1:09.6 | |||
| 5 | 7 | Mario Chávez | ARG | 1:09.8 | |||
| 6 | 2 | Paulo Silva | BRA | 1:09.8 | |||
| 7 | 8 | Cees Kievit | NED | 1:11.3 | |||
| 8 | 1 | Bruce Bourke | AUS | 1:11.4 |
Heat Two
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 5 | Bob Cowell | USA | 1:08.5 | |||
| 2 | 3 | Bert Kinnear | GBR | 1:09.2 | |||
| 3 | 4 | Jackie Wiid | RSA | 1:09.2 | |||
| 4 | 6 | Howard Patterson | USA | 1:09.9 | |||
| 5 | 7 | Paluca | BRA | 1:10.1 | |||
| 6 | 2 | Lucien Zins | FRA | 1:11.5 | |||
| 7 | 1 | Ilo da Fonseca | BRA | 1:11.6 | |||
| 8 | 8 | René Pirolley | FRA | 1:12.9 |
Final (6 August 1948 — 19:00)
| Pos | Lane | Swimmer | NOC | Time | |||
|---|---|---|---|---|---|---|---|
| 1 | 5 | Allen Stack | USA | 1:06.4 | |||
| 2 | 6 | Bob Cowell | USA | 1:06.5 | |||
| 3 | 4 | Georges Vallerey, Jr. | FRA | 1:07.8 | |||
| =4 | 1 | Mario Chávez | ARG | 1:09.0 | |||
| =4 | 8 | Clemente Mejía | MEX | 1:09.0 | |||
| 6 | 2 | Jackie Wiid | RSA | 1:09.1 | |||
| 7 | 3 | John Brockway | GBR | 1:09.2 | |||
| 8 | 7 | Bert Kinnear | GBR | 1:09.6 |