The teenage striker sprung to prominence by claiming the Golden Boot at this year's Under-20 World Cup and extended his prolific vein of form in the Austrian Bundesliga and the Champions League.
Dortmund have completed a transfer coup and possibly secured a decisive boost in a wide-open battle for this season's German Bundesliga crown.
But, as ever when a sought-after player completes a major transfer, there are those pondering what might have been.
Here, we look at some potential winners and losers after the Haaland transfer saga reached its conclusion.
Bundesliga title race
Bayern Munich are chasing an eighth consecutive league title in Germany but their grip on supremacy looks to be loosening at the midway point this time around.
RB Leipzig (more on them later) lead the way from Borussia Monchengladbach, with Bayern four points off the summit.
Halfway into the season, here's where things stand 📊 pic.twitter.com/3LDRy3uF7K— Bundesliga English (@Bundesliga_EN) December 22, 2019
Behind them are Haaland's new employers. Dortmund have struggled for consistency this season but the seven-point gap to Leipzig will suddenly feel a lot more bridgeable. We could see a thrilling run-in.
If Haaland needed proof that a prodigiously talented teenager can thrive at Signal Iduna Park, he did not need to look any further than his fellow 19-year-old.
A veritable assists junkie, England international Sancho will now be supplying the ammunition for a player boasting 28 goals in 22 senior appearances this season.
Håland x Hazard— Squawka Football (@Squawka) December 29, 2019
Håland x Reus
Håland x Sancho
Borussia Dortmund will be must watch in 2020. 🤤 pic.twitter.com/EWm1iXBUj6
Sancho's hopes of a first senior title have now increased. Perhaps more significantly in the long term, so seemingly have his prospects of a blockbuster move to one of Europe's super clubs. Dortmund getting hold of another prime asset means they may be more willing to cash in on Sancho at the end of this season.
Manchester United's forwards
Manchester United were one of the clubs heavily credited with an interest in Haaland. However, it is hard to argue a gifted forward line is the part of an unhelpfully thin squad that most needs attention.
On top of that, Anthony Martial has thrived this season when allowed to operate in a central striking role, and Mason Greenwood appears to be a rare goalscoring talent.
Both of those men might well have found themselves frustrated with Haaland in town.
He might have a forthcoming January saga concerning Paul Pogba on the agenda, but Haaland's high-profile representative is likely to be fairly pleased with his work here.
Numerous reports claim Raiola is a major beneficiary of the outlay being a relatively meagre €20million, stipulated in the player's Salzburg release clause, with other cash freed up for agent fees.
Additionally, Dortmund are unlikely to be Haaland's final destination. If all goes to plan, he might be looking at a €100million-plus move elsewhere in a couple of years that may allow Raiola to feather the nest all over again.
If RB Leipzig were to be denied a first Bundesliga title by a player who joined a rival from their sister club, it would certainly hurt.
A glorious second half of the season for Dortmund may mean some tough conversations within Red Bull's sporting operation.
Looking beyond this term, if Timo Werner's future lies elsewhere, Julian Nagelsmann's side have just missed out on a seemingly readymade replacement.
As a side from the Austrian Bundesliga, selling talents like Haaland for a handsome profit is a vital part of Salzburg's business model.
However, with this deal coming hot on the heels of Takumi Minamoto's similarly cut-price switch to Liverpool, events feel like they are progressing too quickly.
Salzburg's release clauses for the two players appear significantly below market rates, while Hwang Hee-chan is also reportedly on Wolves' radar. After making their mark in the Champions League, Salzburg's status as dark horses in the Europa League is no more.
Aside from the benefits for the likes of Martial and Greenwood, little else about this transfer represents good news for Manchester United.
A lack of success over recent years means it is harder for the 20-time English champions to dine at the top table in transfer terms. Here, there was a chance to secure an exceptional talent at minimal cost.
Then we should consider Ole Gunnar Solskjaer's role. If the manager cannot persuade a player he helped to nurture at Molde, who hails from a country where he is a national hero, how much weight is his talk of United "DNA" likely to hold in future transfer negotiations?