Elde Island has had *many* wars with the Empire, and most people don't
bother to give them distinctive names or numbers, thus making them easy to
confuse.  Hence, as a convenience, I've listed all the references to
different conflicts with Elde Island that I can find:

??? BI
  Dragaerans invade Elde Island for the first time (P 95).  [This may (or
may not) postdate the founding of the Empire.]
  There have been somewhere between 9 and 11 wars with Elde, including one
that happened "during the Ash Mountain uprising" (P 95).
  Elde and Greenaere have had a (several?) wars, but "haven't actually
fought since before the Interregnum" (P 94).
  The ownership of Spaire Island has been disputed between Elde and the 
Empire "for thousands of years" (SL 39).
  Elde has never in "recorded history" tried to invade the mainland,
at least prior to the Interregnum (SL 40).

~176,000 BI
  Sethra helps turn back an invasion from Elde Island (4/11, FH 98).
  Lishni invents the Fire-ram (D 35).  [Presumably a relatively
low-tech(sorcery) tactic, and so tentatively placed early in the
chronology.]

~120,000 BI
  The Empire claims Elde Island for 30-35 years (9/2, LCB 213).

~34,000 BI
  Elde island attacks during a war with the East (15/7, P 95).

~6,000 BI
  Merinna "founded", and under protection of the Kings of Elde.

~2,000 BI?
  Tazendra's great-grandfather made a baron "during the Elde Island Wars"
(Tk 27) [dating speculative].

~1,300 BI
  G'aereth involved in Island Wars, which lead to establishment of
Athyra Emperor Cherova III (PG 30).  Sethra is warlord during the latter
part of these.

~600 BI
  Aerich's father advises Emperor Cherova "on settling matters with the
King of Elde Island" (PG 102).

~50 BI
  The Empire captures Redsky Harbor from Elde ("less than three hundred years ago" (SL 148).
  A five year war with Elde during Tortaalik's reign (FH 30-31).
  The "debacle along the coast that had left an entire district, and one 
critical to Imperial trade, without a liege" (FH 207) may have been 
connected with this war.  It was certainly during Tortaalik's reign.
  "The last time we fought Elde, Greenaere was on our side" (P 94).  [This
is presumably the most recent time there was conflict between Elde and
Greenaere.]

~45 I
  Islanders attempt to invade Adrilankha ("two hunded years ago" PD 138).
Presumably this is the same event referred to as "Reavers" on PD 272-273.
  Elde allows reavers to raid former Imperial shores, while reducing 
Elde's standing army (SL 34, "two hundreds of years" 36).

243-244 PI
  A brief war with Elde, detailed in _Phoenix_.