The Nations Championship returns this weekend as rugby union’s inaugural international competition reaches its exciting autumn finale.

After the first half of fixtures that took place over the summer, the tournament concludes over the coming weeks ahead of a series of finals that all take place at Twickenham.

The pressure is firmly back on Steve Borthwick just a year out from the World Cup despite England bouncing back from their historically awful Six Nations and 45-21 demolition by South Africa with back-to-back wins over below-par Fiji and Argentina.

First up is a visit from old rivals Australia on Sunday, before a reunion with former boss Eddie Jones and Japan, plus a high-profile showdown with the All Blacks of New Zealand.

But what exactly is the Nations Championship and how does its somewhat convoluted format work? Standard Sport explains below.

The Nations Championship is a brand new international rugby union competition that was first announced back in 2023.

It has begun in 2026 after much discussion over the format and will be held biennially moving forward, with the next edition coming up in 2028.

It replaces the old summer tours that saw Northern Hemisphere teams going south for multi-Test series and the autumn internationals, when the Southern Hemisphere nations would then come north to play several games across November.

The idea is to link those international windows and make particularly the summer far more impactful, bringing in an overarching competition that makes every match important.

There is also the new World Rugby Nations Cup that essentially operates as the second tier of the Nations Championship, involving Georgia, Hong Kong, Portugal, Spain, Romania, Zimbabwe, Canada, Chile, Samoa, Tonga, USA and Uruguay, who are split into ‘Europe, Africa and Asia’, and ‘Americas and Pacific’ pools, respectively.

However, there will be no promotion or relegation at all during the first two editions of the Nations Championship - something that has attracted plenty of criticism.

The Nations Championship sees the Northern Hemisphere teams that compete annually in the Six Nations - England, Ireland, Scotland, Wales, France and Italy - pitted against the Southern Hemisphere giants in South Africa, New Zealand and Australia, plus Argentina, Japan and Fiji.

There are two six-team pools, one containing the Northern Hemisphere teams and the other comprised of the nations from the Southern Hemisphere (plus Japan).

However, despite being ranked that way countries do not actually play against the teams in their own pools, but rather contest one game against each nation from the corresponding group.

Those round-robin fixtures take place across six matchdays - three in the summer and three in the autumn.

The Southern Hemisphere teams (and Japan) were at home in the summer, before travelling north in the autumn.

That is all except Fiji, whose home games were held in the UK as their national stadium is not seen as being up to the required standard to host regular Test matches, while there were also commercial considerations. Japan also played against Ireland in Australia.

Once those six matchdays are complete, a finals series takes place across three days in late November - with every match being held at Twickenham in the 2026 edition.

The teams that finished in the same position in each pool will go head to head, culminating in the overall final between the two nations that finished first in their respective pools - with the winners of that match lifting the trophy.

ITV has bought the rights for the first two editions of the Nations Championship in 2026 and 2028, showcasing every match live and free-to-air across ITV1 and ITV4.

They have decided to pause the in-game adverts that proved so divisive during the Six Nations earlier this year, though that is only expected to be a temporary measure.