Wordorigins.org

Wog is a chiefly British word is a holdover from the days of the Empire and is a disparaging term for a non-European, especially someone from India, an Arab, or any other Asian. The origin is not known for certain, but it is widely thought to be a clipping golliwog, the name of a black-faced doll in Bertha Upton’s 1895 book The Adventures of Two Dutch Dolls and a Golliwog:

Then all look round, as well they may
To see a horrid sight!
The blackest gnome
Stands there alone,
They scatter in their fright.

With kindly smile he nearer draws;
Begs them to feel no fear.
“What is your name?”
Cries Sarah Jane;
“The ‘Golliwogg’ my dear.”