## History of the Leica M series The M series began with the Leica M3, introduced by Ernst Leitz GmbH in 1954. It replaced the older screw-mount Leica bodies with a bayonet lens mount, combined the viewfinder and rangefinder into a single bright window, and added a rapid film-advance lever — changes that made it the most influential 35mm rangefinder of its era. The M3 sold over 220,000 units before production ended in 1967, and its body dimensions became the template every later M has stayed close to. A run of mechanical film M's followed: the simplified M2 (1958), the briefly-made M1 (1959, no rangefinder, aimed at scientific/technical use), and the M4 (1964), which refined the film-loading and rewind mechanisms. The M5 (1971) broke from the established shape to add through-the-lens (TTL) metering and was the last M built entirely by hand in Wetzlar using the old "adjust and fit" method — it sold poorly and nearly ended the rangefinder line. Leica pulled the M system back from the brink in 1984 with the M6, which added a built-in light meter while returning to the M3/M4 body dimensions. The M6 (and the later M6 TTL, 1998–2002) became the standard photojournalist's Leica for over a decade. The M7 (2002) added aperture-priority auto-exposure; the manual-only MP (2003) was released alongside it for purists who wanted the M6 experience refined rather than automated. Digital arrived with the M8 in 2006 — a 10.3-megapixel CCD sensor with an APS-H crop (1.33x), not full-frame. The M9 (2009) was the first full-frame digital M, using an 18.5-megapixel Kodak sensor, followed by the M9-P (2011) and the dedicated black-and-white M Monochrom (2012). The M (Typ 240), released later in 2012, moved to a CMOS sensor and added live view and video. The M10 (2017) was a significant redesign: a 24MP CMOS sensor, a body thinned back down toward M3/M6 proportions, and a wider 0.73x viewfinder to address focusing complaints about the M8/M9's 0.68x finder. It spawned a family of variants — M10-P (quieter shutter, no red dot logo), M10-D (no rear screen at all), M10 Monochrom (41MP), and M10-R (40MP color). The current flagship, the M11, arrived in 2022 with a 60.3-megapixel sensor and backward compatibility with nearly the full history of M-mount lenses. Sources: [Leica M3 — Wikipedia](https://en.wikipedia.org/wiki/Leica_M3), [Leica M6 — Wikipedia](https://en.wikipedia.org/wiki/Leica_M6), [Leica M7 — Wikipedia](https://en.wikipedia.org/wiki/Leica_M7), [Leica M8 — Wikipedia](https://en.wikipedia.org/wiki/Leica_M8), [Leica M9 — Wikipedia](https://en.wikipedia.org/wiki/Leica_M9), [Leica M10 — Wikipedia](https://en.wikipedia.org/wiki/Leica_M10), [Leica M11 — Wikipedia](https://en.wikipedia.org/wiki/Leica_M11), [15 years of digital Leica M cameras (timeline) — Leica Rumors](https://leicarumors.com/2021/02/06/15-years-of-digital-leica-m-cameras-timeline.aspx/)