Financial Times No. 14,827 by NEO

Entertaining puzzle this.

Liked  GRENOBLE, ATHEISTS, TATAMI, UTAHAN, ORDER not to mention the whimsical definitions in 8d and 24d. There seem to be quite a few proper nouns. I’m not sure if they are linked in some way or if there is more to them. If you see it, please add a comment.

Thanks Neo for brightening up a gloomy and rainy morning.

Definitions in clues marked like this

* anagram, + charade, – deletion, DD double definition, CD cryptic definition, H hidden, ~ homophone, <- reversal

ACROSS
1 Students on retreat surrender in colourful event (6) SUNBOW [students=NUS<- + surrender=BOW]
5 Manx horse impressive in European city (8) GRENOBLE [horse=GREy + impressive=NOBLE]
9 Satellite from Berlin is between rings! (8) CALLISTO [from Berlin is = IST inside ring=CALL + ring=O]
10 Party wearing dress in warehouse (6) GODOWN [party=DO inside dress=GOWN]
11 As retired, Conservative reportedly achieves enlightened state (6) SATORI [AS<- + ~conservative=TORY]
12 Daytime perhaps existing in Canadian location? (8) MONTREAL [day=MON + Time + existing=REAL]
14 On this, the GLC may provide bedwear (5-7) NIGHT-CLOTHES [ON THIS THE GLC]*
18 UK leopardess makes sound investment (12) LOUDSPEAKERS [UK LEOPARDESS]*
22 Man on river finds disreputable knight (8) FALSTAFF [river=FAL + man(v)=STAFF]
25 New apple approaching apple-pie order (6) NEATER [New + apple=EATER]
26 Soldier shot in mountainous region (6) GILEAD [soldier=GI + shot=LEAD]
27 Is first victim in Paris the wife for Edward? (8) ISABELLA [IS + first victim=ABEL + in Paris the=LA]
28 I hate false saints who don’t go much on religion (8) ATHEISTS [I HATE* + saints=STS]
29 Over in Yachimata, traditionally it’s underfoot (6) TATAMI [H<-]

DOWN
2 American University thanks Chinese native (6) UTAHAN [University + thanks=TA + Chinese native=HAN]
3 Graduate left, cooked noodle, piled on pounds (9) BALLOONED [graduate=BA + Left + NOODLE*]
4 President, shedding weight, available for post-prandial chore (7-2) WASHING-UP [president=WASHINGton + available=UP]
5 Grand mass in Capital Square requires ring (7) GROMMET [Grand + Mass inside capital=ROME + square=T]
6 English lord lines up drink (5) ELGIN [lines up=EL  + drink=GIN]
7 Yellow and red reflected pattern (5) ORDER [yellow=OR + RED<-]
8 Maybe Isaac Newton runs after wife – old woman in pool (8) LAWMAKER [Wife + old woman=MA inside pool=LAKE + Runs]
13 Couple in Longleat Woods (3) TWO [H]
15 Spooner’s reason for getting home after hours? Be ready to surprise (3,2,4) LIE IN WAIT [~getting home after hours=WHY IN LATE]
16 Witness statement more than half-fabricated (9) TESTAMENT [STATE*MENT]
17 Scientist into bats suffers breakdown (8) BOTANIST [INTO BATS]*
19 Ancient god finds position (3) SET [DD]

20 Ace female just succeeded in business (7) AFFAIRS [Ace + Female + just=FAIR + Succeeded]
21 Dalziel’s letters quoted in broadcast confused situation (6) BEDLAM [~Dalziel=dee el=DL inside broadcast=BEAM]
23 Persistent attempt to gain historic seat (5) SIEGE [DD]

24 Scandinavians head down to centre in Peak District (5) ANDES [Scandinavians=DANES with D at the centre]

Thanks to Chalmie @ 3 for pointing out what I missed.