I'm trying to make a level 11 strategist character for a campaign that's coming up soon. Does anyone have any good class/subclass options that would allow me to make such a character? Note that I'm not looking for a build, just for a class and subclass.

Mastermind Rogue, Battlemaster Fighter, and College of Glamour Bard all come to mind.

I would throw Inquisitive Rogues into that list as well. The mechanics fit, and the idea of taking lessons learned through “Inquisitiveness” and applying them to strategic thinking is not far fetched.

Possibly pulple dragon knight fighter, and I actually have made a totem warrior barbarian work for a srategist characters, ad long as you take the wolf ones. The above examples are probably better, especially mastermind and inquisitive.

When I hear strategist, I think someone who's thinking long term, as opposed to a tactician, who would be more about doing things in a particular fight. Are you talking about winning a battle or winning a war?

Battlemaster Fighter is flavored exactly like what you're looking for. It comes with lots of tactical maneuvers for every situation, some of which help coordinate your allies.

Mastermind Rogue is more of a commander. It's all about helping your allies find gaps, coordinate their attacks...and protect you.

College of Valor Bard combines battlefield inspiration with tactical acumen. It should work perfectly if you don't mind using skald's chants instead of shouting orders.

War Wizard or War Domain Cleric could also be a neat choice.

oh right! war wizard! i cant believe i forgot about that! i made a tactical war wizard once.

I would definitely second playing a wizard. You can focus on battlefield control rather than straight damage, allowing you to lean into the strategist roll and dictate the terms of any given fight. 

Not only that, but you can prepare different spell lists for different situations, so with a little scouting/research/snooping, you can ensure you're prepared for any scenario. 

I would give a shot to Order Cleric, their 1st level ability (Voice of Authority) is awesome. Also last UA focused on feats gave us Tandem Tactician, like a better version of the Rogue Mastermind abilities.

Cleric itself has a very good chassis for “battle command” and you can really improve your party capabilities just casting the right spells. Throw some bonus help action to give your allies advantage (from Tandem Tactician feat) and a Bless/Heal to allow your Rogue/Paladin/Striker kick some serious butt!

also inspiring leader feat

This particular campaign has no clerics, and he can't be a wizard for in-game reasons, but the other options look great, and I will sure to check them out. Thank you, everyone! 

Your starting at level 11?

i’ve been playing a war wizard with a 1 level dip into order domain cleric.

the order domain clerics voice of authority feature doesn’t differentiate between spell lists. It also doesn’t restrict the spell to buffs. Doesn’t even require saving throw failure or pass, merely that they are subjected to the spell.

if you want to get a 1st level bless off on the party at the begining of the fight, you can do so Probably on the first turn of combat. Bless makes whoever you choose More accurate for that reaction attack. If you choose yourself for the saves, you reduce the likelihood of you needing arcane deflection for a saving throw too. An effective use of a first level slot, especially if you may be fighting weaker enemies.

and if you happen to need to AOE an area which your martial happens to be in... they can make a reaction attack if they leave. Bonus points if it’s a rogue with evasion who dodged your fireball to sneak attack anything else that lives. Not really a go to option, but better than some alternatives and can be partially planned around resistances.