Species name: Typha angustifolia
Common name: Narrowleaf Cattail
There is a bit of debate as to where this species originated, but I'm going to give it the benefit of the doubt and say it's a North American species that has been introduced to Europe. It's entirely likely it happened the other way around; the species is so broadly distributed across the Northern Hemisphere that it has become difficult to tell where it "has its roots," so to speak. All cattails are what are called "obligate wetland" species, meaning that they require the wetland environment in order to grow. This doesn't mean they need to have the base of the plants submerged; it just means that they require very loose, very wet soil to grow with poor drainage. They have adapted throughout the millennia to be able to survive having water-logged roots, where most plant species would essentially drown. Even though roots grow underground, they still require oxygen to survive!
Cattails have a long history of use in North America, from food to clothing and baskets. Almost every part of the cattail is edible, with the youngest parts being favoured. Even though the plant doesn't ever grow true wood, it still can get "woody" (like bamboo; that's not real wood, either) and difficult to chew. The underground rhizomes can be eaten like potatoes, and were once thought to be "the next great agricultural crop" when the whole world floods after the ice caps melt. This idea was rather quickly abandoned since, well, they're not all that tasty. But in a pinch they're actually quite nutritious, even more than a potato or sweet potato. If you're ever lost in a wetland and about to die of starvation, go dig up some cattail rhizomes! Just make sure you cook them; they're incredibly unpalatable when raw, and some even report they might be mildly poisonous. Best not to risk it.
I remember when I was a kid we used to go pick the green leaves to make grass skirts out of for "Hawaiian Day" at day camp. I thought we did that only because we don't have palm trees in Canada, but it turns out that they have been used for exactly that purpose for hundreds of years. Granted, they're not called "Hawaiian grass skirts" when you're not in Hawaii (or using grass...). The reeds are also fantastic for making baskets. Weave the green leaves while still fresh, then allow to completely dry. The basket will be lightweight, can get wet without falling apart, and floats. Great for collecting cattail rhizomes! The leaves can also be woven into a flat mat, laid on a flat rock then pounded flat with a smaller rock. Once all of the leaves have been split open and the fibres have all been mashed together, the sheet is let dry. The dried sheet can be written on exactly like paper would have been, but this material is much more durable. It's actually the exact same method that ancient Egyptians used to make papyrus, where we get the English word "paper". I'm not sure whether the method for making paper this way was independently discovered in North America, or whether word had spread from Europe during the early days of exploration.
Due to disappearing wetland habitat around the world, all cattails are at risk for population decline. To compound this fact, there are some "facultative wetland" species (species that don't require wetlands to survive, but can grow perfectly well there) that outcompete cattails for resources and habitat space. Unless we actively start ripping out invasive aquatic plants and conserve wetlands, this species is at a real threat of disappearing.