As economic power and population shifted from rural farms to industrializing cities in decades around 1900, Britain and Germany changed how their parliaments were defined. US legislature hasn't made that shift in representation and probably should. This is going to be contentious.
As Britain pioneered the industrial revolution, Manchester's population exploded. A center for industrialization, Manchester grew to become the UK's third largest city (after London and Glasgow) by 1901. Between 1700 and 1800 it grew from fewer than 10,000 to about 90,000. Manchester's population doubled between 1801 and 1820 and then doubled again by 1850.
Yet when it began its growth, Parliamentary representation was granted to districts. Manchester did not even elect its own Members of Parliament (MPs) in the early 19th century. It was just part of the Lancashire district.
Meanwhile, in "rotten boroughs," a paltry few could elect two MPs. How few? In one borough, 7 voters got to elect 2 MPs. Dunwich had literally fallen into the sea, leaving just 32 voters clinging to land; they, too, got to elect 2 MPs. In a sense, this was representation by acreage.
The economy changed how population and power was distributed. Industrialization brought workers into cities like Manchester and left behind smaller populations in the little rural communities that - in part thanks to industrialization - needed fewer people to raise crops and tend livestock. While the population and economies of cities grew, their political representation had not.
This changed in the UK (the disparity between Dunwich and Manchester began to be addressed with legislation in 1832) and, later, in Germany, Austria and France through a series of parliamentary reforms starting in the early 1800s and continuing through the first world war. As the economy shifted from agriculture to industrial, as the important factor shifted from land to capital, these communities shifted political power to give voice to the members of this new economy.
The need for such a shift in the US is less dramatic. At least in the House. Divided into 435 districts by population (obviously a number that grows every decade), the US is not going to have anything as egregious as 7 people electing two representatives.
Nonetheless, the Senate is still structured around the notion that acreage deserves representation. Like the early forms of British parliament that found themselves antiquated by urbanization and industrialization, the US Senate gives disproportionate representation to owners of land rather than capital or knowledge. Two states, Wyoming and Vermont, have populations smaller than Washington DC. Those states have four senators and DC has none. 21 states with a population of 36 million get 42 senators; California with a population of 39 million gets 2 senators. In one part of the country, you are just one of 850,000 voices your senator must represent; in another, you are one of 19.7 million voices
California has helped to pioneer the information and entrepreneurial economies and that has made it successful in industries like aerospace, communications, silicon, software, biotech, and the internet. Of the 100 most valuable companies in the world earlier this year, the market cap of companies in California represented $4.2 trillion of the US's $14.1 trillion (and of the world's $21.2 trillion). California represents 12.4% of the American population and 30% of the value of the country's biggest companies. Like Manchester in the early 19th century, California's lead in creating jobs and wealth has not yet translated into commensurate representation.
In 1790, when the US was founded, 90% of workers were in agriculture. Acreage was a pretty good proxy for good representation at that time. Agriculture now employs fewer than 2% of American workers. Acreage is now a terrible approximation of how representation should be calculated. (And yes, I know that technically the Senate is a way to represent states not acreage but it does effectively do that. State representation does not follow people around as they move; states "govern" over a constant and stable area, not a constant and stable population. What this effectively means is that Senators represent acreage.)
As it now stands, the politics in the US is going to be disproportionately defined by the least populous and least affluent areas of the country because of how the Senate is structured. It's hard to imagine us ignoring that for too much longer or imagine that addressing this issue will ever be easy.