17 June 1990
On 17 June 1990, Nelson Mandela visited Ottawa, Canada escorted by his then wife Winnie Madikizela Mandela. He travelled to Canada a few months after his release from 27 years of imprisonment. The visit was part of a six week tour of 14 nations in Africa, Europe and North America that began on the 6 June 1990. As he stepped onto the red carpet he was greeted by Canadian Prime Minister Brian Mulroney. In his speech, at the airport, he thanked the Canadians for keeping the economic and political pressure on South Africa to end Apartheid.  
References

The Times-News, (1990), Canada Greets Mandela, from Google News,18 June [online], Available at www.news.google.com [Accessed:11 June 2014]