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The different periods in Albert Einstein’s life are generally well documented, except for the Milanese period, a key one for the understanding of Einstein’s training and for the development of his scientific questioning. From 1895, first in Milan, then in Pavia, Einstein benefitted from the scientific supervision of his uncle Jakob, and was able to consult electrotechnical journals, whose content were important to him both in a technical and in a theoretical perspective. While being a student at the Eidgenössische Technische Hochschule (ETH) in Zurich from 1896, he then returned regularly to Milan to meet his family for the holidays – where he could work on the most recent articles in physics at the rich library of the Lombardo Institute, Academy of Sciences and Letters, as can be established from his letters to Mileva. Yet, Einstein did not work in isolation during his stays in Milan between 1899 and 1901 because he met regularly his faithful friend and collaborator, Michele Besso, whom he had first known in Zurich. Einstein discusses scientific issues with him almost every day, some in connection with a first thesis on molecular forces, others on the relative motion of matter and ether, or on light processes and the nature of radiation, etc. As regards the Einstein-Besso relationship, the Milanese period therefore acted as a prelude to the famous period in Bern beginning in 1904, during which they met daily. Einstein also benefitted, through Besso, from the scientific environment of his uncle Giuseppe Jung, a professor of geometry at the Milan Politecnic Institute. A cross-analysis of the journals present at the library of the Lombardo Institute and the content of Jung’s personal library, provides new insights into Einstein’s relation to him and to Besso. It also makes possible an approach to Einstein’s ideas in relation to the available scientific literature. Hopefully, this new perspective will help to trace back his scientific ideas, « false tracks » included. The need to expand his doctorate work (in April 1901), the experiment devised by him to detect the Earth’s motion through the ether, and perhaps even a first idea of light quanta as early as 1901, may be consequences of Einstein’s readings and discussions in Milan in the spring of 1901.