Mortars, How Early?

[Kevin Renner]

How early could we see mortars of the infanrty support type? Not the monsters seen in the 19th century. And just what would the effects be on infantry tactics?

 

[The Dean]

I think the crucial thing for the man portable mortar to be developed was a reliable percussion cap for the firing pin on the base plate to ignite. So around 1830 would be the earliest you could see them.

They would certainly have been useful in the Crimea and the American Civil War.

 

[Minchandre]

I'd add that good steel is necessary, too, if you want a mortar small enough to be man-portable (the impression I got from the OP was something on the order of a 60mm mortar; a weapon with a crew of two or three that can be carried by a single human, but must be set up to fire).

Good enough steel limits us to the end of the 19th century at the earliest, I think.