Work on the Leopard started in 1956 in West Germany. At the time, West Germany had only just re-established a military after its defeat in WW2 and was equipping its tank arm with US-built M47 and M48 tanks, but the desire for a German-built tank was very much there.

By July 1957, a set of requirements had been drafted for this tank:
– Weigh no more than 30 tons
– Have a 30 horsepower per ton ratio
– Multi-fuel engine with air-cooling
– 350km driving range
– Best possible suspension
– Maximum width of 3150mm
– Ground pressure of 0.8kg/cm²
– Armour penetration capability of 150mm at 30° between 2000 and 2500m
– Ammo capacity like US-built M47/48 in service
– Armour protection for close-in defence against 20mm fire.
– NBC protection
– 24h fightability

A focus was put on mobility over protection and firepower, as it was anticipated that developments in ammunition penetration and lethality would outpace armor development. Thus, a priority was set on not getting hit in the first place, through the vehicles ability to maneuver.

France, meanwhile, had just come out of its failed AMX-50 program and was very interested in the German concept. They would join the development program in June 1957. Just over a year later in September 1958 Italy would also join the program. In 1960, the 3 German design bureaus were to submit their prototypes for field testing. But even before that in 1959 it had been decided that improvements had to be made to the submitted designs. For these “Phase 2” designs Team A (Porsche, MAK, LW, JJ) had to build 26 units and team B (Warnecke, Ruhrstahl, Hanomag, Henschel) only had to build 6. Of those 6 team B only managed to complete 2 in the required time.

In 1961, 50 more prototype 2 models from team A were ordered. This 0-series came with a redesigned cast turret and several changes to the shape of the hull to provide more room for the engine compartment, allowing for a better internal layout. This would create the iconic exhausts on the back of the hull. At the same time, it was decided that an optical range finder would be added to the turret, adding the bumps to the turret sides. France would meanwhile fail to meet program deadlines.

In addition to this, there was a disagreement over the gun that the tank would use. Germany wanted the British L7 105mm gun while France pushed for their own CN 105 F1 105mm gun. As a result of these delays and disputes the French were dropped from the program. France would go on taking the lessons from the Leopard program and use them in their AMX-30. Later in February of 1963, the Team A offering would officially be selected as the winner of the program and the then Defense minister announced that he would ask the defense committee in Parliament for approval to start production of this tank.

At this point the tank came in at 40 tons and would cost an estimated 250.000 USD to build (roughly 2,5 million USD adjusted for inflation). In July 1963 an order for 1.500 units was placed by the West German Defense Ministry. Production was setup at Krauss Maffei in Munich starting in 1964. The first production batch would be delivered between September 1965 and July 1966.

The Leopard would also see massive export success within the young NATO alliance and its allies.
– 1968 Belgium
– 1969 The Netherlands
– 1971 Norway
– 1971 Italy
– 1976 Denmark
– 1976 Australia
– 1978 Canada
– 1982 Turkey
– 1983 Greece

In total 80 pre-series vehicles and prototypes, 4.744 Main Battle Tanks and 1.741 utility and anti-aircraft vehicles would be built for a total of 6.565 Leopard 1 and vehicles based on Leopard 1.

Let us now talk about variants.

  • A1; Production batches 1-4 saw several updates including a new gun stabilizer, side armor skirts, new thermal jacket for the gun, improved engine filters and a change to different style of tracks.
  • A1A1; An A1 with additional armor fitted to the turret made by Blohm & Voss. All previous 4 production batches would be updated to this standard.
  • A2; The first 232 units of the fifth batch received a heavier turret with improved side armor.
  • A3; The last 110 vehicles in the 5th batch received a welded turret that improved protection over previous turrets with similar side protection as the A2 with an increased internal volume.
  • A4; The sixth batch of 250 vehicles received the same welded turret as the 1A3, but with a new integrated FCS and the new EMES 12A1 gunners sight. The commander meanwhile received the PERI R12 independent sight with night vision capability.
  • A5; In 1980, a research program was started to develop further upgrades to the Leopard 1. It was decided that the tank would receive a modern fire control system and fully effective night/bad-weather vision system. The resulting upgrade package would be installed on Germany’s 1.225 Leopard 1s, featuring the EMES 18 fire control system based on the Leopard 2’s EMES 15 and included a thermal sight for the gunner.
  • A6; A proposed further upgrade based on the A5 with the Leopard 2’s 120mm cannon, CITV for the commander, add-on armor effective against 125mm ammunition and IR signature suppression. This was rejected based on the poor weight distribution and limited cost effectiveness.
  • 1A5BE (covered for its relevancy to Ukraine); In 1968, Belgium would become the first foreign customer of the Leopard. Dubbed the Leopard BE (later 1BE) 324 units would be ordered. These were practically identical to those in the 1st German production batch. In 1974, they would start to be equipped with a new SABCA FCS (AVLS), a HR Textron-made stabilizer for the main gun and a thermal sleeve for the gun, designated 1A3BE. In 1987 Belgium awarded a contract to SABCA and OIP to develop a modernization package for the 1A3BE. OIP would develop a new gunner’s sight that included a thermal option while SABCA would develop the TFCS. This package would be adopted as the 1A5BE.

    132 1A3BEs would be upgraded to 1A5BE standard, of which 64 would remain in service in 2014 when they were decommissioned. In 2015/16 they were sold off at scrap price to OIP Land Systems, where until recently 56 where stored. Rheinmetall would end up buying 50 of these 1A5BEs from OIP to fulfill a contract with the German government to deliver Leopard 1 tanks to Ukraine. 6 to 7 meanwhile made it across the Atlantic, ending up in the hands of private collectors in the USA. 6 units are owned by Drive Tanks and 1 I spotted up for sale not long ago.
  • 1A5DK(covered for its relevancy to Ukraine); Denmark would purchase 120 Leopard 1A3s from Germany in 1974. These were designated Leopard 1DK. In 1992 as part of “Cascade aid” Denmark would acquire an additional 110 Leopard 1A3 from Germany, whom had to reduce the number of tanks it owned rapidly to comply with the “Conventional Forces Europe” treaty.

    Denmark would contract STN ATLAS Electronik to supply 230 EMES 18 FCS for their fleet of Leopard 1DK/1A3. These were installed between 1990 and 1994, converting these tanks to 1A5DK. The 1A5DK would be decommissioned and replaced with the Leopard 2A5DK in 2005. In 2010, they sold their last 100 stored models to the German FFG.
  • Biber; An armored bridge laying vehicle based on the Leopard 1 chassis that carries a 22m long bridge that could take loads up to MLC60.
  • Leguan; An armored bridge laying vehicle based on the Leopard 1 chassis that carries a 26m long bridge that could take loads up to MLC80.
  • BergePanzer 2; An armored recovery vehicle based on the Leopard 1 chassis. The vehicle is equipped with a crane that can lift 35 tons (can be increased to 70) and it could carry a spare Leopard 1 power pack on the rear deck.
  • BergePanzer 2 AEV; An altered version of the BergePanzer 2 to fill the pioneer role. Storage was added for explosives that would be used in obstacle clearing and a drilling auger would be carried on the back instead of a Leopard 1 power pack.
  • PioneerPanzer Dachs; An armored engineering vehicle equipped with a telescoping excavator arm installed where the BergePanzer 2’s crane would be.
  • NM189 ingeniørpanservogn(covered for its relevancy to Ukraine); An armored engineering vehicle based on the Leopard 1 developed in Norway between 1995 and 1999. 22 of these would be build.
  • Wisent-1; A family of modern support vehicles built on the Leopard 1 chassis meant to support the Leopard 2 in a “cost effective” way. The 3 variants are an armored recovery vehicle, armored engineering vehicle and mine clearance vehicle.

Ukraine has been pledged a large number of Leopard 1 MBTs and Leopard 1-based support vehicles from its allies.

  • 100 Leopard 1A5DK from Denmark, the Netherlands and Germany
  • 55 Leopard 1A5/1A5BE from Germany
  • 30 Leopard 1(variant not specified) from Denmark
  • 21 BergePanzer 2 from Germany
  • 1 BergePanzer 2 from Norway
  • 29 Biber from Germany
  • 5 Biber from the Netherlands (and an unknown number from Denamrk)
  • 5 PioneerPanzer Dachs from Germany
  • 42 Wisent-1 from Germany (and an unknown number from Denamrk)
  • 3 NM189 Ingeniørpanservogn from Norway

For a total of 185 MBT and at least 106 support vehicles. As of writing this the 44th Mechanized Brigade has been the first to be seen training on Leopard 1A5DK. The 22nd Mechanized Brigade has meanwhile been seen using the Biber in training recently.

The original Twitter thread.
The list of heavy equipment donations to Ukraine compiled by Jeff.