Caley Thistle were relegated from the Scottish Premiership, despite finishing the campaign with a 3-2 victory against Motherwell.
The Inverness side have spent 12 of the last 13 years in the top flight but Hamilton’s 4-0 victory against Dundee means they will be playing Championship football next term.
Richie Foran’s side netted three times in the space of four minutes with Greg Tansey’s opener followed by a quick-fire Alex Fisher double.
Motherwell substitute James McFadden pulled one back for after netting with his first touch after replacing Louis Moult.
Ryan Bowman converted an injury time penalty for the visitors after Craig Clay was brought down by David Raven.
The Caley Jags held on for the win but it was not enough to prevent the Highlanders from finishing bottom of the table.
Inverness were unchanged from the team that defeated Dundee 2-0 at Dens Park on Wednesday, while Motherwell made three changes with Lionel Ainsworth, Allan Campbell and Shea Gordon replacing Scott McDonald, Keith Lasley and David Ferguson.
There was plenty of pressure on the hosts but they settled quickly and threatened first with Louis Laing testing Russell Griffiths with a fierce drive after 10 minutes.
Motherwell went close five minutes later with Lionel Ainsworth twisting and turning in the penalty area before dragging a left-footed effort inches wide.
Inverness were looking the more likely and Ross Draper curled over from just inside the penalty area after good work from David Raven.
Motherwell full back Chris Cadden almost netted a spectacular opener for the visitors when he ran half the length of the pitch before firing over just before the interval.
The Caley Jags improved after the break and went close after 56 minutes when Gary Warren nodded wide from a Greg Tansey corner.
Tansey, who has signed a pre-contract agreement with Aberdeen, got the game’s opening goal after 64 minutes when he fired beyond Griffiths from the edge of the area.
The hosts doubled their advantage only two minutes later when Fisher was in the right place to slot home from a Draper effort that was heading well wide.
The Caley Jags forward had the ball in the back of the net only a minute later when he flicked home a Draper knock-down to give Richie Foran’s men a three-goal advantage.
Motherwell pulled one back after 73 minutes when substitute James McFadden nodded home with his first touch after an Elliot Frear drive had struck the crossbar.
The Steelmen were awarded a penalty in injury time when Craig Clay was bundled over by David Raven and Ryan Bowman slotted home.