Monaco produced one of those mixed-up races that the principality is sometimes famous for, with the full wet, intermediate and slick tyres used - at one point with all three types of tyre on track at the same time.
The race was won by Red Bull's Sergio Perez from third on the grid using three tyre changes, with strategy at the heart of the outcome in extremely variable conditions. The race was declared after 64 laps, running to the maximum time limit as a result of earlier delays.
The race also featured a safety car followed by a red flag period, adding to the strategic complication caused by a drying track. All the drivers began the delayed race on the full wet as per the rules for a start behind the safety car, but as the track dried out many switched to the intermediate - with the timing of this first stop becoming very influential to the final outcome.
An unpredicted heavy rain shower before the start meant that the race got underway in 21 degrees centigrade ambient and 31 degrees of track temperature: considerably cooler than the previous days.
As a result, drivers and teams had to react to changing conditions as they encountered them - trying to leave their options open as to whether to switch to the intermediate or slick after the first full wet stint.
A red flag meant that the second half of the race effectively turned into a sprint to the finish, with drivers allowed to change tyres in the pits. The tyre choice here was influenced not only by the conditions but also by the tyres that each driver had at their disposal from their allocations.
Scuderia Ferrari was unable to turn Saturday's front row qualifying into the result it was hoping for and had to settle for 30 points, courtesy of a second place for Carlos Sainz and a fourth for Charles Leclerc in what was a particularly frustrating race for the Monegasque driver.
On lap 16, the first of the front runners to pit and switch from Wet to Intermediate tyres was Sergio Perez. Leclerc made the same change two laps later, as did Max Verstappen.
Sainz however, stayed out until lap 22, switching straight to slicks and it was decided to do the same with Charles, calling him in at the same time for a double stop.
This played into Red Bull's hands as Sergio Perez managed to get ahead of Carlos and Verstappen did the same with Charles.
The race was more or less over at this point, although it was stopped one more time after Mick Schumacher had a huge accident at the swimming pool, from which he fortunately emerged unscathed. The F1-75 was faster than its rivals but the positions remained unchanged.
"When you start with your two cars on the front row and you don't win, it means something went wrong from our side. I think we made a few poor decisions and we paid the price. I am sorry for Charles, because it's his home race, so it was particularly important for him, as indeed it was for all of us," Mattia Binotto, Team Principal & Managing Director.
Mercedes driver, George Russell rounded out the top five, gaining one position during the race, passing Lance Norris after the switch to dry tyres. Russell struggled with right front graining in the final laps.
"It was tough on the medium in the second part of the race, with a lot of graining towards the end, but P5 is still a decent result," said Russell.
Alfa Romeo F1 Team ORLEN brought home two points with Valtteri Bottas, ninth at the chequered flag. Zhou Guanyu finished 16th.
BWT Alpine F1 Team's Fernando Alonso made it back-to-back points-scoring finishes after taking seventh place.
Esteban Ocon crossed the line in ninth, but a five-second time penalty for causing a collision meant the Frenchman left without scoring points as he finished in twelfth place.
Williams Racing's Nicholas Latifi finished 15th whilst teammate Alex Albon retired from the race.
Latifi stopped on lap two to change to the intermediate tyre, whilst Albon stopped on lap 18 for the hard tyre. A puncture forced another change just four laps later, this time the Thai driver taking the medium compound.
After the red flag period ended for the Schumacher crash, Albon was forced to retire on lap 50.
Pos Driver Team Laps Gap
1 Perez Red Bull 64 1h 56:30.265
2 Sainz Ferrari 64 + 0:01.154
3 Verstappen Red Bull 64 + 0:01.491
4 Leclerc Ferrari 64 + 0:02.922
5 Russell Mercedes 64 + 0:11.968
6 Norris McLaren 64 + 0:12.231
7 Alonso Alpine 64 + 0:46.358
8 Hamilton Mercedes 64 + 0:50.388
9 Bottas Alfa Romeo 64 + 0:52.525
10 Vettel Aston Martin 64 + 0:53.536
11 Gasly AlphaTauri 64 + 0:54.286
12 Ocon Alpine 64 + 0:55.644
13 Ricciardo McLaren 64 + 0:57.635
14 Stroll Aston Martin 64 + 1:00.802
15 Latifi Williams 63 + 1 Lap
16 Zhou Alfa Romeo 63 + 1 Lap
17 Tsunoda AlphaTauri 63 + 1 Lap
Albon Williams 48 Retired
Schumacher Haas 24 Accident
Magnussen Haas 19 Water Pressure
Fastest Lap: Norris (McLaren) 1:14.693 (Lap 55)