| Roles | Competed in Olympic Games | |
|---|---|---|
| Sex | Male | |
| Full name | Jan Herman "Caius"•Welcker | |
| Used name | Caius•Welcker | |
| Born | 9 July 1885 in Alkmaar, Noord-Holland |  NED |
| Died | 13 February 1939 (aged 53 years 7 months 4 days) in Schiedam, Zuid-Holland | NED |
| Affiliations | HVV Quick — Den Haag (The Hague), Zuid-Holland | NED |
| NOC | Netherlands | NED |
| Medals | OG |
| Gold | 0 |
| Silver | 0 |
| Bronze | 1 |
| Total | 1 |
Welcker, who formed the famous right wing of his club side Quick and the national team with Edu Snethlage, won 15 caps, scoring five times.
| Games | Discipline (Sport) / Event | NOC / Team | Pos | Medal | As | |
|---|---|---|---|---|---|---|
| 1908 Summer Olympics | Football (Football) | NED |
Caius Welcker | |||
| Football, Men (Olympic) | Netherlands | 3 | Bronze |
