The Ranfurly Shield, colloquially known as the Log o' Wood, is perhaps the most prestigious trophy in New Zealand's domestic rugby union competition. First played for in 1904, the Ranfurly Shield is based on a challenge system, rather than a league or knockout competition as with most football trophies. The holding union must defend the Shield in challenge matches, and if a challenger defeats them, they become the new holder of the Shield.
Three unions held the Ranfurly Shield between 1910 and 1919. Due to the outbreak of World War I, however, no matches were played between 1915 and 1918.
| Union | Won | Successful defences | |
|---|---|---|---|
| Held at beginning of decade | 11 | ||
| 16 August 1913 | 6 | ||
| 10 September 1914 | 5 |