Ben Stiller
Larry Daley

Carla Gugino
Rebecca

Dick Van Dyke
Cecil

Mickey Rooney
Gus

Bill Cobbs
Reginald

Jake Cherry
Nick Daley

Ricky Gervais
Dr. McPhee

Robin Williams
Theodore Roosevelt

Kim Raver
Erica Daley

Patrick Gallagher
Attila the Hun

Rami Malek
Ahkmenrah

Pierfrancesco Favino
Christopher Columbus

Charlie Murphy
Taxi Driver

Steve Coogan
Octavius

Mizuo Peck
Sacajawea

Kerry van der Griend
Neanderthal #1

Dan Rizzuto
Neanderthal #2

Matthew Harrison
Neanderthal #3

Jody Racicot
Neanderthal #4

Paul Rudd
Don

Anne Meara
Debbie

Martin Christopher
Lewis

Martin Sims
Clark

Randy Lee
Hun #1

Darryl Quon
Hun #2

Gerald Wong
Hun #3

Paul Cheng
Hun #4

Teagle F. Bougere
Teacher (Mike)

Pat Kiernan
TV News Anchor

Nico McEown
Friend #1

Meshach Peters
Friend #2

Matthew Walker
Politician

Jason McKinnon
Irish Worker

Jono Lee
Chinese Rail Worker

Jason Vaisvila
Viking

Brad Garrett
Easter Island Head (voice)

Crystal the Monkey
Dexter

Che Landon
Pretty Tourist Girl (uncredited)

Phil Proctor
Moose (uncredited)

Gary Sievers
Viking Warrior (uncredited)

Owen Wilson
Jedediah Smith (uncredited)

Darren Shahlavi
Roman (uncredited)

Miraida Rios
(voice actor)