This wheel arrangement came to be known as the Pacific type after the voyage the completed locomotives had to make across the Pacific Ocean to New Zealand. A few instances of the 4-6-2 wheel arrangement are known to have existed prior to 1901, but these were all reconstructions of locomotives that were originally built with a different wheel arrangement, thereby making the thirteen members of the Q class the first "true" Pacifics in the world.
The 4-6-2 wheel arrangement, known as the Pacific type, was named after the journey it took to New Zealand.  While some examples existed before 1901, they were reconstructions of locomotives with a different original design, making the thirteen Q class locomotives the first true Pacifics ever built.