"I'm very proud of the team, we showed real character out there today under a lot of pressure," he said. "We have worked really hard over the last few months and you get what you deserve.
"We stuck at things and never gave up and when we had the opportunity we looked dangerous. Today was about winning and sending a message that we are one of the top teams in the world and we have done that.
"But I do have to take my hat off to the Welsh public today. They really turned up, we all know about the current economic conditions but they came and it made a massive difference."
Wales continue their World Cup warm-up schedule with a tie against Argentina next Saturday before Gatland and his coaching team have to name their final 30-man squad for rugby's showpiece event in New Zealand.
Argentina, who finished third in the 2007 World Cup, can expect a much changed line-up according to Gatland.
"Next week is going to be big for our confidence," he added. "There will be a lot of changes and a lot of experience coming in. Hopefully people like Gethin Jenkings and Adam Jones will feature and it's a nice position."
Tickets for Wales v Argentina are available priced at £20 for adults and £15 for children and are being offered on a 'buy one get one free basis'.
Tickets can be purchased from www.wru.co.uk or via the ticket hotline 02920 230130.