とて

1. 1Even (someone or something expected to be an exception); X is no different from others.Ex. 1
2. 2Even if (one does something or something is the case), it changes nothing; the effort is futile.Ex. 2

A literary, written-style pattern found in essays, speeches and formal prose, and rare in casual conversation. The main clause typically denies an expectation or states that nothing can be done. In speech, たところで, にしたって or としたって are more natural, while といえども is a similar but even stiffer written alternative.

• といえどもN1「といえども」 is close to 「とて」 when attaching to nouns, and the two are often interchangeable. It is more formal, common in speeches and regulations, often takes a prohibition or obligation in the following clause, and can also attach to minimal quantity words like 「一円」 to mean 'not even the slightest amount'.
• としたって / としたところでN1「としたって」/「としたところで」 similarly mean 'even someone...' and 'even assuming..., it's useless', with nearly the same meaning, but they lean colloquial. When expressing a stance with a personal noun, 「としたって」 is generally used; in formal writing, use 「としても」 instead.
• にしたってN1「にしたって」 has a similar meaning but is casual spoken language; the following clause is usually a judgment, volition, or criticism, and it can attach to interrogatives to mean 'no matter'. Since 「とて」 is literary and archaic with a following clause that is usually a helpless negative result, the two differ in register and should not be interchanged.
• たところでN1「たところで」 is similar only to 「とて」's use after verbs and adjectives; it attaches to the ta-form of verbs and means 'doing it is in vain', in which case the two are often interchangeable. It does not attach to nouns, is neutral in register and used in speech too, and can also mean 'at most'.
• にしろ / にせよN2「にしろ」/「にせよ」 also express concession, but the following clause is usually a judgment, claim, or demand and can be positive in content; they can also list alternatives as in 「AにしろBにしろ」. 「とて」 is more archaic, its following clause is usually a helpless negative result, and it is not used for listing.
• であれ / であろうとN1「であれ」 attaches only to nouns, interrogatives, and na-adjectives, and cannot attach to verbs. It often pairs with interrogatives to mean 'no matter who/what', and the following clause is usually a judgment, resolve, or obligation, not limited to negative results.

N+とて is close to the more formal といえども and to the conversational としたって/としたところで and にしたって, while Verb+たとて corresponds to the everyday たところで. にしろ/にせよ and であれ/であろうと typically mean 'whether X or Y' or 'regardless of X', rather than singling out one unexpected case.