We look at where Ireland, England, Wales and Scotland stand following a thrilling month of three-Test series in the southern hemisphere, live on Sky Sports...
Ireland's history makers; England deliver when needed
Ahead of the summer tours, there were very few people within and outside rugby circles who gave Ireland a realistic chance of beating the All Blacks in New Zealand, even less that credited them with a chance of winning a series.
Come the end of a breath-taking three Tests, however, Ireland achieved almost the unthinkable: overcoming the All Blacks in New Zealand for the first time in their history, claiming a sensational 2-1 comeback series victory, and moving to No 1 in the world rankings.
Even when considering Ireland's dominant display in their victory over New Zealand in Dublin during November, to travel to the home of the All Blacks and compete the way they did - producing displays full of control, pace, stellar handling, and defensive brilliance - far exceeded what most would have expected.
Losing the first Test after a bright start, and after suffering defeat to the Maori All Blacks in their first tour game, had some pundits predicting Ireland would lose all five games on tour.
In the end, they overcame New Zealand two weeks on the trot - the first time the All Blacks have lost two successive home games for over two decades (1998 vs South Africa and Australia), and also beat the Maori All Blacks at the second time of asking to end the tour with an overall winning record too.
A quirk in World Rugby's decision to base Rugby World Cup draws on seedings from years previous means the top four in the world are all on one side in Ireland, France, South Africa and New Zealand. Andy Farrell's men should hold no fear anymore, though, and now undoubtedly have the tools to aim for a first-ever Rugby World Cup semi-final appearance.
For England, there must be a curious mix of feelings come the end of their 2-1 series win vs the Wallabies.
On the one hand, there is the sense it was more an aversion of disaster than a massive moment, but on the other, there is excitement and hope at the young players Eddie Jones and co brought through on tour as they - like Ireland - fought from 1-0 down to win 2-1.
England, and particularly Jones, were under pressure travelling to Australia after a second successive Six Nations in which they lost three of their five games, and were then ripped apart 52-21 by the Barbarians at Twickenham.
That pressure ratcheted up even more when England contrived to lose the opening Test vs 14 men after Darcy Swain's red card and a number of early injuries to Australia. Thereafter, there is a real possibility England's second Test win to keep the series alive may well have saved Jones' job.
A narrow third-Test win with Marcus Smith to the fore sealed a much-needed and morale-boosting series win, but there remains glaring concerns with Jones' England.
Their clear power advantage should really have seen them defeat the Wallabies with little trouble, but each game saw them wobble and cede momentum in leaking scores.
Too often, Jones' side have been stunted in attack, deployed too much kicking, and been a team riddled with indiscipline, but when they needed to deliver in Australia, they secured the series.
Courtney Lawes looks to be England's captain for the World Cup, Ellis Genge has emerged as a key leader, Owen Farrell made a successful return, while several young players displayed their talent: Jack van Poortvliet, Henry Arundell, Guy Porter, Tommy Freeman, Will Joseph and Ollie Chessum all travelled with no Test experience, but each played parts in series victory.
England's maul too looks to be a really potent force. Jones and co have 13 Tests to go before the World Cup in France, during which they will host New Zealand and South Africa in November, France in the Six Nations and travel to Cardiff and Dublin.
Some tough assignments await. Can they kick on from here?
Wales give South Africa a scare; Scotland throw series away vs Argentina
Travelling off the back of a pretty horrendous 2022 Six Nations showing - during which they lost four of five games, including to Italy in Cardiff - Wales were expected to face the Springboks in a three-Test series and get soundly beaten in each match.
The series did not pan out that way at all, however, with Wales more than competitive in each game, and by the end, will feel they may have left a potentially historic series win behind them.
Facing a supremely confident - verging on arrogant - Springbok camp, a Wales side with nothing to lose raced out to a shock 18-3 half-time lead in the opening Test, only to eventually lose 32-29 due to an agonising Damian Willemse penalty with the final kick - and that after Wales went down to 13 and then 12 men in the closing stages.
The second Test saw Wales turn the tables as a late Josh Adams try and stunning Gareth Anscombe conversion off the touchline confirmed a dramatic and deserved 13-12 success - Wales' first ever vs the Boks on South African soil.
In the third Test, Wales remained firmly in the game until two minutes to go, pushing the Boks the whole way before ultimately falling short as two Handre Pollard penalties stretched the scoreboard.
But for a side who floundered during the Six Nations in attack, and seemed incapable of keeping teams out with power and pace like Ireland, England and France, Wales gave themselves and head coach Wayne Pivac much hope this summer with their displays.
They opened up a famed South African defence to score tries in each Test, and proved they aren't yet a side to completely right off.
For Scotland, familiar failings came back to haunt them unfortunately: Positive, enterprising play putting them in a position to achieve something, but defensive incompetence and lack of concentration seeing it slip from their grasp.
Facing undoubtedly the weakest opponents of the southern hemisphere's Rugby Championship nations in Argentina, this summer was a real chance for Scotland to travel abroad and seal a Test series victory against a Tier-1 nation.
So often during this particular Test window, Scotland don't get the chance to face one of New Zealand, Australia and South Africa, with Ireland, England, Wales and France seemingly on rotation, but despite the opportunity that presented itself for Gregor Townsend's men against the Pumas, they threw it away.
Abysmal in a first Test 26-18 loss, Scotland got back on the horse to claim a dominant 29-6 second Test win and seemingly set themselves on course for success in the series-decider.
By the 50th minute, they'd built a commanding 15-point lead at 28-13 ahead, ripping through for four tries in the process, yet all they could muster for the remainder was a single penalty as Argentina rattled off three more converted tries, including the winner from Emiliano Boffelli in the final play.
Talented, but maddingly inconsistent, Scotland remain a few skips away from being able to be termed challengers on rugby's biggest stage.
Ojo: Jones still under pressure, England's brilliant youngsters, Ireland the performance of any series
Former London Irish and England wing Topsy Ojo spoke to Sky Sports News on Monday, picking out some of the key points as he saw them.
Amongst his thoughts, Ojo is not convinced England head coach Jones is out of the woods yet as far as pressure and his position is concerned.
"There's always pressure. In any high-profile coaching job there's always pressure.
"I think it allows him to enjoy his summer a bit more, to be like: 'Right we've got the win, there'll be less critics coming for my head,' but he'll know that England need to keep progressing.
"Because the autumn will roll around very quickly, they've got New Zealand and South Africa coming, Argentina and Japan, all to Twickenham, and if they go and don't perform well in those games, more pressure comes back on him.
"He'll understand they've made a good step forward, they've made some progression, young players have got some really good experience, but there's a lot of hard work coming up in the autumn, into the Six Nations and then on to the World Cup."
Ojo on England's young players in Australia, and excitement for the future...
"Those two boys [Henry Arundell, Will Joseph] have been brilliant, and to think they actually went out there as apprentice players, so weren't exactly part of the squad.
"How they performed in training, how they carried themselves was brilliant.
"For Henry to score with his first touch was incredible. That acceleration, 0-100 in such a short space of time and then the footwork, it's incredible. And that's a moment that he will have forever.
"He's been brilliant, Will Joseph has been brilliant, Jack van Poortvliet as well, Guy Porter, Tommy Freeman, these are a lot of young guys making their debuts and first starts on this senior tour.
"So when you talk about the depth England are building and the talent coming through, this is what these guys can produce.
"That's what will make those guys [England coaches] most pleased. And even speaking about Marcus Smith, he's still building up his caps, Freddie Steward is still building experience and only just finishing his first year in Test rugby.
"The feeling these guys will have after this win, this is going to be the group that takes England forward not just to the World Cup but beyond. It's exciting to see what they can do, and we just want to see more of that now."
Ojo: Ireland the performance of any series; They've thrown their hat in as World Cup challengers...
"It's [2023 World Cup] going to be incredible. Ireland's was the performance of the weekend, and probably the performance of the whole summer series.
"The way they did it, the manner in which they did it. Very physical, very abrasive, and really took it to a New Zealand team in a manner we've probably not seen in a very long time.
"Ireland were clear and above better in the way they played, the way they attacked New Zealand in attack and defence, thoroughly enjoyed making history and have massively put their name in the hat as one of the contenders going forwards for the World Cup.
"They sit top of the tree now, alongside France who have been impressive as well. You factor in other nations will get better and will improve and compete, but for Ireland to go down to New Zealand and do something they've never done before, in the manner they did, is what's hugely impressive.
"They are really setting a standard at the minute. It was a great way to start the full day of international Test rugby we had on Saturday."
Hartley: Southern Hemisphere vs Northern Hemisphere divide has closed | Greenwood, Alphonsi: World Cup prospects exciting
Sky Sports Rugby's Dylan Hartley on the Southern Hemisphere vs Northern Hemisphere divide in rugby...
"In terms of the divide, it's closed. The power is in the North. The South are still there but I think if we had a World Cup tomorrow, we've got genuine contenders in Ireland, genuine contenders in France and the All Blacks you never write off.
"You've got the World Champions being South Africa, England can upset, Wales can upset.
"There are so many contenders and we haven't even talked about the rules and regulation changes when you look at Piutau playing for Tonga, Fiji…it's simmering away nicely.
"World Rugby is in a good spot."
Sky Sports Rugby's Will Greenwood...
"I feel the calibre of France, Ireland, Scotland are now scoring tries whereas before were just a defensive and disruptive unit.
"Wales have four or five worldies in their team who are brilliant competitors who will stare anyone down.
"At the moment, Northern Hemisphere rugby is in fine fettle."
Sky Sports Rugby's Maggie Alphonsi...
"You forget also there's Fiji sitting 11th and Italy in 12th just below the top 10 so there are still teams that could really push themselves into it.
"The World Cup is going to be really exciting. I love the fact the top four keeps changing around [in the rankings].
"It's great to think that international rugby is at its most competitive and building up to what is going to be an exciting year, we want teams really fighting it out and looking like anyone can win that World Cup next year.
"2026 will move to a new Nations Championship which will be much less about three-Test series and back to different games against different individuals.
"Three-Test series are a true measure of a team; it's not a one-off plucky win and it's not an underdog turning over the favourite.
"You get three weeks to analyse a team, work out trends, you've got to adapt and have strength in depth if you get injuries or cards with a ban."