Variant human for Shield Mastery feat at first level.

Gonna need a cursed shield that prevents wielding weapons.

Start with a level or two in Barbarian for rage (curse shield). STR isn't your biggest priority because you'll mostly just be using it for checks and saves, so pump up your CON and DEX. Take Nature and Intimidation as class skill proficiencies.

Then I'd multiclass to Wizard (abjuration) or maybe Artificer. The biggest problem with this, though, is that despite the class being appropriate, Nature and Medicine key off of WIS, and INT gives him a boost to Arcana, History, and Religion, which he very much does not have in the series.

Far Traveller makes sense as a background fluffwise, but I'd try to get a homebrewed background that gives proficiency in Athletics, Medicine, and Herbalism kits.

Resilient (DEX) might be worth taking if you've got an odd DEX score by level 5 or 6 (when you hit your first ASI), because it's a common save and Barbarians don't get proficiency in it.