I recently came across the term encampment. Although I could understand that the word must be very close related to camp, it bugs me that I don't understand why such a long word for the same thing exists. Is encampment a more sophisticated word than camp? The translation for both words refer to the same words in my mother tongue (german).
As literal nouns these words are synonymous, though "camp" is by far the more common term to describe a location for and collection of temporary accommodations and related activities. In modern usage, "encampment" is usually reserved for military contexts (and even there is rare and used for spice).
As a verb, the words differ: "to camp" is to engage in the activity of camping, i.e. "to go and live in a camp or as campers"; "to encamp" is specifically to "set up a camp".
But perhaps the biggest difference is that "camp" is used synecdochically to mean "the people of a camp", and by extension, metaphorically to mean "the members of a particular [often political] party". "Encampment" is never used this way (it always means the camp as a whole; the location, the structures, the people, the activity; but never only "the people").
Bottom line: contemporary English speakers almost always use "camp" today; the only time we'd use "encamp" is as a verb, to specifically describe the activity of "setting up a camp". The only time we'd really use "encampment" is as a colorful synonym for camp, almost always in a military context.
Encampment has more of a military feel to it, similar to bivouac. A military camp may be called an encampment, whereas the tent you pitch by a fire site in a national park is merely a camp, or a campsite.
When I was in the Civil Air Patrol, encampment referred to the two weeks in the summer spent on an Air Force base, during which the cadets received training in various Air Force activities, including flying and various other activities.