World Rugbys 12-team Nations Championship launched in 2026, uniting Six Nations sides with Rugby Championship teams plus Fiji and Japan; tournament splits six fixtures across northern and southern hemisphere from July-November before Finals Weekend at Twickenham on November 27-29. It has been labelled a "tectonic shift", set to shake up the world of rugby union, but what is the Nations Championship, what have been the results so far, and what is the.