18 April 1982
Immediately after obtaining independence from Britain in 1980, Zimbabwe embarked on the process of renaming its cities, towns and streets. This was an attempt by Zimbabwe to eradicate all symbols associated with the British colonialism and White minority rule. On the second anniversary of independence,18 April 1982, Zimbabwe renamed its capital city Harare, after the Shona chief Neharawa. The initial name of the capital was Salisbury, named after the British Prime Minister 3 rd Marquess of Salisbury.  
References

Crwflags.com,Harare(Zimbabwe),[online],Available at www.crwflags.com [Accessed:11 April 2014]