The concept of "local content" has been around for a long time and Australia was probably ahead of the pack back in the thirties. Local content requirements were mandated by national governments, usually in concert with stiff tariffs or even an outright prohibition of built-up vehicle imports. The idea was to create local manufacturing capability and the jobs that go with that capability while at the same time reducing or even eliminating the drain on the country's foreign trade balance of payments that high value automotive imports represent. Often it took place in countries where there were already assembly plants (Argentina, Australia, Brazil, Canada, and France are all examples).
In some countries with small vehicle markets, like Uruguay, for example, the attempt to impose local content requirements led to an effective end of the availability of new cars for all but the truly wealthy who could afford to pay for the huge import taxes imposed on imports, which helps explain why walking around the streets of Montevideo in the mid seventies was akin to walking the streets of a U.S. city in the late 'thirties (judging from old movies).
In countries with historically modest car markets, this led to much longer product life cycles than in markets where the greater sales volumes justified the investments required. The decades-long life of the sixties' model Ford Falcon production in Argentina and Australia are examples of that characteristic of markets where local content requirements were extreme.
As markets grew and governments started to dismantle trade barriers through the creation of regional trade blocks, bi-lateral and multi-lateral trade agreements, and tariff reductions, many local content requirements evolved into regional arrangements like in western Europe, where engines were produced in one country, transmissions in another and assembly in several all for the entire trade block. The same ultimately became a reality in Argentina and Brazil via the Mercosul trade agreement. In Canada, the Auto Pact led to the demise of the unique-to-Canada models such as the Monarch and Meteor and eventually the Auto Pact was displaced by the North American Free Trade Agreement which imposes no local content requirements per se.
In some countries like Australia and to some extent New Zealand, the reduction/elimination of tarliffs and other barriers to the importation of built-up vehicles in recent decades is in some quarters seen as unfair to those companies (like Ford and GM, aka Holden) who played by the rules of local content and made the local investments in plant and equipment that entailed for decades only to have the doors thrown open to imports from mass producers in Asia at prices that could not be matched by the relatively-low volume operations of the local automobile manufacturers. Ultimately, this led to a severe retraction of local automotive manufacturing.
It is complex subject and the experience varied considerably by country and by decade. The above is but a very brief start.