Disney has officially closed the books on its long-awaited merger with Hollywood powerhouse 21st Century Fox in a monumental $US71 billion ($100 billion) deal.

The content acquisition expansion deal was finalised on Tuesday night (US time), signalling Disney’s transition from an entertainment giant into a genuine content colossus, as it now holds an estimated 35-40 per cent market share.

It prefaces Disney’s impending move into the online streaming market to challenge tech giants Netflix and Apple with its offering, Disney+.

“This is an extraordinary and historic moment for us — one that will create significant long-term value for our company and our shareholders,” Disney CEO Bob Iger said in a statement.

“Combining Disney’s and 21st Century Fox’s wealth of creative content and proven talent creates the pre-eminent global entertainment company, well positioned to lead in an incredibly dynamic and transformative era.”

The deal marries Disney’s eclectic cast of characters, such as perennial fan favourites Mickey Mouse and the hugely popular Marvel comic superheroes, with Fox’s stable – including The Simpsons, Avatar and Family Guy.

Disney’s line-up has greatly expanded following the merger deal. Photos: supplied

It could spell a further expansion to the already sprawling Marvel Comic Universe, with the X-Men franchise and outcast antihero Deadpool freed from their ransom at Fox.

Deadpool star Ryan Reynolds was particularly overjoyed by the prospect of a new life on Disney, sharing a ‘school photo’ to celebrate the occasion.

Feels like the first day of ‘Pool. pic.twitter.com/QVy8fCxgqr

— Ryan Reynolds (@VancityReynolds) March 19, 2019

However, several projects – such as The New Mutants – could be placed on hold as Disney works through the opening stages of its new model.

The Simpsons showrunner Al Jean also commemorated the historic business ploy, sharing a new cartoon poking fun at the merger.

Jean has indicated the long-running animated series, which has now notched up 30 seasons, could finish within the first couple of years of its new ownership.

.@TheSimpsons Thank you Fox and welcome Disney! pic.twitter.com/01uPrPsf7r

— Al Jean (@AlJean) March 19, 2019

“In terms of milestones, I thought if it ended it would be 30, but it didn’t—we’re doing 32—so now, I think the biggest variable is we’re obviously going to be a Disney property, and what Disney wants to do with the show,” Jean has said.

Disney says that its new business configuration could create an additional $US19.3 billion ($27.2 billion) in annual revenue.

But there are questions over the job security of employees from both individual companies, with reports of potential layoffs affecting as many as 4000 employees.

However, media analyst Rich Greenfield predicts there could be further “bloodshed” as the two studios amalgamate, estimating that figure could be closer to 8000 job cuts.