What's the reason to have an dagger lorewise?

[Michanicks]

Disclaimer - not gameplay wise. I know it has nice looking finishers.

For open combat sword is better in everything, it's longer, safer to block/parry (due to length) and does more damage (again due to it's bigger length). That's also the reason why do i not like to seing guards with a daggers, sometimes with a literal kitchen knives.

Dagger is more stealthy and convinient, but hidden blade is much-much better at it: easier to hide, takes less space, harder to lose (it's literally your bracer), easier to use in unconvinient spaces and poses (like hanging from ledge).

In real life people used dagger instead of hidden blade because latter was more expesive, more complex, easier to break and not very strong (due to being mechanical). But if you have working hidden blade - then do why you need the dagger?

[ulrich lady killer]

thought the same but still bought that ♥♥♥♥

[skitzbuckethatz]

I love using the dagger

[本夹明SPenguin]

Lore-wise, it looks real nice when forcefully planted into the top of someone's skull.

edit: looks and SOUNDS nice too

[Basan™]

Because in Middle Age's days Daggers were one of the few weapons that you could manage to toss and decently control while throwing. And that coupled with being more stealthier than Swords. Never forget that Hidden Blades never were too much common in those days because their mechanical needs tended to make'em unreliable when used for long periods of time (i.e., breaked and required more maintenance to keep'em working properly).

[Yinkho]

IRL blocking is more something you'd want to do with a dagger and not a sword: a longer blade could break more easily, so to avoid that you have to block the base of the adversary's blade with the base of yours. Because a long piece of sharp blade is always dangerous whether it's he's or yours: IRL friendly fire is an issue! :))
So, lorewise, maybe they tried to have the character(s) make realistic choices?

[Basan™]

Atm, I'm not recalling if upon AC II we had a lot of choice when it came upon the Daggers dept., but I do recall that upon AC: Brotherhood until I've unlocked Altair's Swords (through side activities development), the Dagger options were always better to face the Ciento Occhi burglar's gang stealing attempts from you.
Perhaps it's similar in AC II, since I haven't replayed it in a long, looooong time now.

[Kazden Soza]

The main difference was more of a game play reason than lore. The main game play benefit of the dagger was that it was faster than the sword and could attack more enemies if fighting a large group. A lore reason to use the dagger is if you are fighting in tight quarters where swinging a sword would be impractical. I tend to use daggers only against the enemies that dodge a lot.