Solving time approx 16 mins.

I spotted 10 winners of the Nobel Peace Prize - I think that’s all there are in it. And of course 8dn gives a strong hint to the theme. A lot of the featured Nobel laureates are given brilliant &lit clues, e.g. 1,22; 6; 11; 16; 20,27.

Across
1,22 MARTIN LUTHER - the founder of Protestantism, and presumably after whom Martin Luther King was named. King was winner in 1964.
4 A(r)CADIA - an old name for the French bit of Canada.
9 GO,RE - ??? - The answer’s right, as Al Gore’s the latest recipient of the Prize. I can see green=GO, which just leaves and=RE, red stuff=GORE. There must be a better explanation. [ And so there is - as pointed out by Owen and Paul, Al Gore is a Green, so it's simply a double definition. ]
11 WALESA - S,E inside A LAW, all reversed. Winner in 1983.
13 BEFRI(brief*),ENDS - not sure how “assists with” is a definition of befriends though.
15,18 MARY CELESTE - great anag &lit.
17 EVACUATES - “set a U cave” reversed.
25 TUT,U - “you” - is it permissible to do a homophone of a single letter when it’s pronounced completely differently in the word? This is another Nobel laureate - Desmond Tutu won it in 1984.
26 ACT(OR)S

Down
1 MO OR AGE
2 REEVE - hidden in fREE VErse. The Reeve’s Tale is one of the Canterbury Tales.
3 1,SO,LA,TE - three consecutive notes of the scale.
5 C,ARTER(y) - maximum speed=C (the speed of light). Jimmy Carter won it in 2002.
6 DALAI LAMA - “A Mali a lad” all reversed. Winner in 1989.
7 AMNE(name*),STY - Amnesty International were winners in 1977.
8 PEACE DIVIDEND - cryptic definition, and what might be the puzzle’s title.
14 ROOSEVELT (role votes)* - winner back in 1906.
16 MAN,DEL,A - very good &lit clue for the 1993 winner.
19 ELECT(R)A - a play by Euripides.
20,27 MOTHER TERESA (at Rome there’s)* - another great &lit.

An excellent puzzle from Dac, one of the top setters. Solving time: 21 mins

* = anagram

ACROSS

8 GNAR (L) ED This has to be right, I think, esp with the L in a crossing down clue, gnarled being defined as twisted. So it’s l in (danger)* if I’ve read it right. That gives l = live, which is not in either Concise OED or Chambers. I thought it might mean l = live from electricity but a quick look at Wikipedia yielded nothing.

9 E (tip of rose) YE (you) SPOT (find evidence of) Such a well-crafted surface.

14 SOR (BONN) E University in Paris. Bonn, capital of the Federal Republic of Germany up to reunification and indeed a city, not just “a small town in Germany”. American in clue as, Concise OED confirms, sore = angry is a mainly US usage, though it’s familiar as such to me.

19 POM-POM

26 I (CE = engineer BOA = stole) T It = Italian the anagram of stole initially tempted.

27 ST (E (WART) G) RANGER Alien = stranger. wart = skin blemish in eg = say

DOWN

1 HIGH-RISE FLATS IS = one’s in (a fresh light)* See 9 across.

2 WHATNOT (that now)* an unspecified item

3 YELLOW FIN(e) Always a pleasure to work out a new word from wordplay. Chicken = cowardly = yellow

4 (f)UND ONE (appearing as itself) ‘is’ is a link. Definition = ruined F = fellow

5 F (EEL-G) OOD This, I think, turns ‘glee’ upside down in ‘food’. I was not sure though if the ’surge’ indicates this or the ‘tucking’. I suspect the former as tucking in looks like a straight containment indicator.

10 THE (a) TER MINATOR(y). Nmsindy weakness on films was no problem here. The separation of ’short’ from ‘menacing’ by a comma did cause a pause for thought though. The letters removed are indicated by “bans” and “short” respectively.

15 BUONA SERA (Good evening in Italian) (on a bus are)* Was not sure of the spelling here at first and had to wait for across words to be solved.

16 B (EGg) ETTER

20 P(OP S)ONG Slightly uneasy surface suggesting hospital problems, so it was nice to move into the separate world of the wordplay. Definition is ‘charts number’ though I suppose every pop song does not get there.

21 AS (Martin-Luther) KING