The comic book-based blockbuster's nearest challenger was The Chronicles of Narnia: Prince Caspian, which started its international roll-out with a promising estimated $20.7m from 2,000 screens in 12 mostly smaller territories.
All films in the marketplace were helped by a break in the hot weather that had kept Northern Europeans in particular away from cinemas last weekend.
Zooming past the $200m mark, Iron Man grossed an estimated $20m from 4,609 locations in the 58 territories handled by Paramount Pictures International (PPI), $1m from the 526 screens in the single territory handled by Sony Pictures Releasing International (SPRI), and another $4.6m from territories handled by other distributors.
PPI reported a drop of only 5% in the UK, where the Marvel production remained at number one with a gross of $3.7m from 479 locations, for a cumulative territory take of $25.6m.
In Australia, the film dropped 30% but still held on to the number one slot with a gross of $2.2m from 218 locations, for a territory total of $13.8m.
Top spot was also retained in Brazil, where the 25% drop led to a $1.3m gross from 255 locations, for a territory total of $10.7m.
Korea produced $2m from 358 locations, Mexico $1.3m from 408 locations, and Italy $1.2m from 321 locations.
SPRI reported a gross of $1m from 526 screens in Spain, for second place in the market and a territory total of $10.3m.
Walt Disney Studios Motion Pictures International (WDSMPI) said family fantasy sequel Prince Caspian, produced by Disney with Walden Media, opened 27% better than its predecessor did in the same group of markets (and 14% better than Iron Man). Launched during the winter holiday of 2005, the first Narnia film, The Lion, the Witch and the Wardrobe, went on to gross $453m internationally (compared to $291.7m in North America).
Opening day-and-date with its chart-topping domestic launch, Caspian took an estimated $7.5m from 700 screens in Mexico, 36% better than the first film. Russia produced $5.6m from 700 screens, 53% better than the first film. And Korea delivered $3.5m from 300 screens, 1% better than the first film.
Other strong performances came in India ($935,000, 57% up on Lion), Malaysia ($924,000, 18% up), Panama ($800,000, 55% up) and Indonesia ($651,000, 27% up).
Fox International's What Happens in Vegas continued to play well outside the US, earning an estimated $20m from 4,200 screens in 56 markets over its second international weekend. The rom-com's international total climbed to $55m.
In the UK, Vegas was up 22% to $3m from 405 screens, for a territory total of $7m. In Germany, it was up 36%, taking top spot with $2.6m from 509 screens, for a total of $5.7m.
Spain produced a top-ranking $2.3m from 410 screens (total $6.7m), Australia $1.9m from 334 screens (total $5.2m), Russia $1.4m from 476 screens (total $6.6m), and France $1.3m from 306 screens (total $5.1m).
Big budget disappointment Speed Racer dropped a modest 30% in Western Europe and 32% in Latin America to gross an estimated $7m (representing 1.3m admissions) from 4,700 prints in 39 markets, reported Warner Bros Pictures International (WBPI). The film's international total has reached $24.4m after two weekends.
The family action outing took an estimated $1.1m in Brazil (for a local total of $2.8m); $1m in Mexico (total $4.1m); $803,000 in the UK (total $1.7m); and $725,000 in Korea (total $4.3m).
SPRI's Made of Honor grossed an estimated $5.7m from 2,085 screens in 25 markets, for an international total to date of $19.6m.
The romantic comedy opened in Germany with $1.5m from 502 screens (for second place in the market), in Brazil with $1m from 142 screens (also for second place) and in five smaller territories.
Card counting drama 21 took an estimated $3.8m from 1,415 screens in 40 markets, said SPRI, for an international total of $46m.
The film opened in Australia with $1.4m from 191 screens and in Taiwan with a chart-topping $660,000 from 60 screens.
Universal's rom-com entry Forgetting Sarah Marshall grossed $1.5m from 694 dates in 10 territories, raising its international total to $21.8m.
It opened in Sweden with an estimated $135,000 (expected to be good enough for top spot in the market) from 24 dates.
In the UK, the film was up 7% from its second weekend with $1.1m from 393 dates, for a 17-day total of $12.8m.
WBPI's The Bucket List grossed an estimated $1.4m (representing 125,000 admissions) from 560 screens in 25 markets, for an international cumulative total of $72.5m.
The comedy held on to number two spot in Japan by grossing an estimated $1.3m (100,000 admissions) from 233 screens, for a local running total of $5.2m.
Nim's Island grossed $1.1m from 552 dates in the three territories handled by Universal. The family fantasy has amassed $10.5m so far in Universal territories and $26m in all markets.
SPRI's Prom Night grossed an estimated $800,000 from 300 screens in four markets, for a total to date of $3.3m. The horror remake opened in Spain with $685,000 from 226 screens.
Universal's acquisition (for four territories) Doosmday took $473,000 from 258 dates over its second weekend in the UK.
The studio's Definitely, Maybe grossed $325,000 from 340 dates in 22 territories and raised its international total to $20.5m. It opened in Italy with $90,000 from 100 dates.
Also from Universal: In Bruges took $320,000 in the UK, for a local total of $9m; The Other Boleyn Girl grossed $232,000, raising its total in the studio's territories to $32.8m; Untraceable took $165,000 from 196 dates in seven territories, for a Universal total of $10.9m and an overall international tally of $14.5m; and Step Up 2 The Streets took $130,000 from 150 dates in the studio's five territories. The dance drama sequel has now grossed $38.2m for Universal and $85m overall internationally (compared to its predecessor's $49m).
Fox's Shutter grossed $742,522 from 504 screens in 20 markets, opening in Australia with $373,204 from 72 screens. The international total for the thriller stands at $15.5m.
The studio's Street Kings grossed $718,936 from 701 screens in 32 markets, for a running international total of $29.1m; Horton Hears a Who! took $502,194 from 1,500 screens in 17 markets, for a total of $136.8m; and The Darjeeling Limited took $102,563 from 50 screens in four markets, for a total of $21m.