Southern Nigeria was a British protectorate in the coastal areas of modern-day Nigeria, formed in 1900 from union of the Niger Coast Protectorate with territories chartered by the Royal Niger Company below Lokoja on the Niger River.

The colony around Lagos was added in 1906, and the territory was officially renamed the Colony and Protectorate of Southern Nigeria.

In 1914, Southern Nigeria was joined with Northern Nigeria to form the single colony of Nigeria.

Postage stamps

Initially using the postage stamps of the Coast Protectorate, in March 1901 a set of nine values, depicting Queen Victoria in a 3/4 portrait, went on sale. The Queen was soon succeeded by her son Edward VII, necessitating a new issue of stamps, which came out in 1903. The design, a profile of the King, continued in use throughout his reign, with changes of color, watermark and paper. The 1p value was redrawn in 1910, and is distinguishable by the "1" in "1d" being thinner, while the "d" is taller and broader.

In 1912, the vignette was replaced with a portrait of George V, for a set of 12, with values ranging from 1/2p to 1 pound.

The lower values of these stamps are inexpensive, while the shilling values range up to US$100, with genuinely used stamps being worth more than unused. The rarest stamp is the 1-pound value of 1903, priced at around US$300 used.