The name has two explanations, and the second proves itself. The first derives it from limes, boundary: in early medieval charters the place is Lemiate, and the term was given to fortified frontier lands. The second, proposed by Olivieri, derives it from Terrae Alibiatae, flooded lands — and indeed the old centre still floods punctually whenever the Garbogera stream swells. In the town's arms, at the bottom, there is a golden bee: it is Napoleonic heraldry, and it is there for a stay of a few weeks.
That stay, though, carries weight. At Mombello, in 1797, Napoleon held court with Joséphine in the villa Pusterla Crivelli Arconati, built in 1754 by Francesco Croce in a medievalising style; and within those rooms were decided the birth of the Cisalpine Republic, the end of the Republic of Venice and the fall of Genoa, and the groundwork was laid for the treaty of Campoformio. In the villa's private chapel, on the fourteenth of June that year, Paolina Bonaparte married general Leclerc. Then the villa gave its name to another story: the psychiatric hospital of Mombello, opened in 1878, was the largest asylum in Italy — forty thousand square metres of buildings laid out like a small village, following Pinel's idea that asylums should stand inside villages. Through it passed the painter Gino Sandri, the photographer and film-maker Luca Comerio and Mussolini's illegitimate son. It was the last to close after the Basaglia law of 1978. The rest is the Brianza of the Groane: protected heaths, farmsteads, and the old tramway that goes to Milan.