In Mike Duncan's Revolutions podcast about the French Revolution, he talks about Napolean leaving his army (probably tens of thousands of people) behind in Egypt after things didn't go well and he departed for France.
The podcast mentioned some scientific advancements introduced to the area by the French, like the printing press, but it didn't go into great detail.
What happened to all these people left behind in Egypt? Were they on their own to find their way back to France? Or did they stay in Egypt permanently and settle a French colony? Was the area radically altered by the huge number of French soldiers that were left behind, and if so are there any signs of this presence today?
Napoleon left the army in mid 1799, under the command of General Kléber who had success at Heliopolis and Cairo. Kléber was assassinated and Menou inherited the command, which more or less marks the end of French successes.
Menou suffered a series of losses in battles and sieges. He finally surrendered with his remaining 10,000 men on September 2nd 1801. The instrument of surrender included an agreement by the British to repatriate and transport the surrendering French.
That said, I've never read any detailed description of when or how precisely the repatriation happened. But Menou was back in Paris by May 1802. So it would have happened between the French surrender in early September 1801, and May. So they didn't get back to France for 2 1/2 after Napoleon.