Case Study: Changing Population and Diversity in a Named Place

Birmingham: a growing city in the West Midlands

Birmingham, in England’s West Midlands, provides a named example of changing population structure and ethnic diversity since 2001. The figures here describe the Birmingham local authority area, rather than the whole surrounding urban area.

After population decline during much of the late twentieth century, Birmingham returned to growth. Its population rose from about 977,000 in 2001 to 1,073,000 in 2011 and 1,144,900 in 2021. That is an increase of approximately 17% over twenty years.

Population size tells us how many people live in a place. Population structure tells us about its composition, including the proportions in different age groups. A city can therefore grow while also becoming older or more diverse.

A relatively young population that is also ageing

During the early 2000s, population estimates indicated that Birmingham’s working-age population, aged 15–64, was increasing while the combined population aged under 15 and 65 or over was declining. Later census comparisons show that its age structure continued to change, but not simply towards a younger population.

Between 2011 and 2021, Birmingham’s median age increased from 32 to 34 years. Median age is the age dividing the population into two equal halves. Despite this increase, Birmingham remained relatively young: England’s median age was 40 in 2021, and Birmingham had the lowest median age of any local authority in the West Midlands.

The age-group figures reveal what changed beneath this overall comparison:

The number of residents aged 50–64 increased by about 30,900, while the number aged four and under fell by about 6,900. Birmingham was therefore still youthful compared with England, but ageing between 2011 and 2021. Its growing total population did not mean that every age group grew.

Ethnic diversity has increased since 2001

Ethnicity describes how people identify with a cultural background, heritage or ancestry. Birmingham already had substantial ethnic diversity in 2001, partly reflecting earlier migration from South Asia and the Caribbean. Subsequent censuses show a further change in its ethnic composition.

These are selected groups, not the whole population, so the columns do not total 100%. The White British share fell substantially, while Pakistani, Bangladeshi, Black African and Mixed groups formed larger shares. Change was not uniform: the Black Caribbean share fell from 4.9% in 2001 to 3.9% in 2021.

In 2021, the wider White category accounted for 48.7% of residents. This includes White British and other White groups, so it must not be confused with the 42.9% White British figure.

Migration and births help explain the changes

Birmingham’s universities, including the University of Birmingham and Aston University, attract students from elsewhere in the UK and overseas. Students and young professionals help maintain a relatively young population. Young families and births have also contributed to population growth.

International migration has included arrivals from Pakistan and India, African countries such as Somalia and Nigeria, and Eastern European countries such as Poland and Romania. People move for work, education, family connections or safety. These movements have contributed to increasing diversity alongside births within established communities.

The overseas-born share of Birmingham’s population rose from 16.6% in 2001 to 26.7% in 2021. This supports the importance of international migration, but birthplace and ethnicity measure different things: someone born in Birmingham may identify as British Pakistani, for example.

Overall, Birmingham became larger and more ethnically diverse after 2001, while remaining relatively young despite an increase in median age during 2011–2021.

Named place: Birmingham, West Midlands

• Population: about 977,000 in 2001 → 1,073,000 in 2011 → 1,144,900 in 2021; approximately 17% growth since 2001.

Population structure

• Early 2000s: working-age population increased while the combined younger and older dependent population declined.
• Median age: 32 in 2011 → 34 in 2021, compared with England’s 40 in 2021.
• 50–64-year-olds: 14.4% → 16.2%; under-fives: 7.6% → 6.6% during 2011–2021.
• Conclusion: relatively young, but ageing, with uneven changes between age groups.

Ethnic diversity since 2001

• White British: 65.6% → 42.9% in 2021.
• Pakistani: 10.7% → 17.0%.
• Black African: 0.6% → 5.8%.
• Mixed groups: 2.9% → 4.8%.
• Overseas-born: 16.6% → 26.7%; birthplace is not ethnicity.

Drivers

Universities attract students; work, family and safety attract migrants; births contribute to growth. Overall: larger, more diverse and still relatively youthful.