The Oberon class were considered an improved version of the preceding Porpoise-class submarines, with a different frame of the pressure hull[2] and constructed from a better grade of steel.

The boats carried 258 tons of oil giving them a range of 9,000 nautical miles (17,000 km; 10,000 mi) at 12 knots.

[9] In an effort to take the subs from anti-submarine warfare training to frontline service, Maritime Command developed a refit program that included new sonars, periscopes, communications and fire-control systems.

[16][17] On 11 April 1962, the purchase was announced in the House of Commons of Canada by the Minister of National Defence, Douglas Harkness.

[21][22] The United Kingdom, in an effort to get the contract moving, offered the hulls of Ocelot and Opportune, but Canada passed on them.

[26][27] The submarine was initially ordered for the Royal Navy as HMS Onyx, with Chatham Dockyard laying the keel down on 27 September 1962.

[34] Ojibwa underwent her SOUP refit beginning in 1979, arriving at HMC Dockyard at Halifax, Nova Scotia on 18 June for preparation.

[35] Following the SOUP refit and the introduction of the Mark 48 torpedoes, the Oberons were considered fully operational and counted the same as other offensive fleet units in Maritime Command.

[36] Following the end of the Cold War, the Oberons were retasked, performing patrols on behalf of federal institutions such as the Department of Fisheries and Oceans and the Solicitor General of Canada between 1991 and 1994.

[33] In 1994, Ojibwa was cut in half; her engines were removed and replaced with newer ones from HMS Osiris, which had been purchased from the Royal Navy as a source of spare parts in 1992.

[26][37] During the Turbot War, the Oberons were tasked with monitoring European fishing fleets off the Grand Banks of Newfoundland.

[40] On 11 June 2010, it was reported that Ojibwa would be moved by BMT Fleet Technology Ltd to become part of the collection of the Elgin Military Museum at St. Thomas, Ontario.

[41] On 2 December 2011, it was announced that the Department of National Defence had approved the transfer of Ojibwa to the Elgin Military Museum[42] subject to satisfaction of financial requirements.

She stayed in Hamilton at Heddle Marine Dockyards being repainted and fitted with specialized transport cradles that would allow her to be moved across land.

[43] On 18 November 2012, Ojibwa, on the barge HM 08, made the final leg of her journey by way of the Welland Canal and then Lake Erie from Hamilton to Port Burwell, while being towed by the tugs Lac Manitoba and Seahound.

[44][45] The sub arrived in Port Burwell on 20 November after a short journey and became part of a new Museum of Naval History.

[46] During April 2015, financial issues dealing with the transfer of the submarine to Port Burwell were widely circulated, as Royal Bank of Canada called on the community to pay the $6 million loan.