Photographer Jamie McGregor Smith has spent the last five years capturing brutalist and modernist churches across Europe. Here, he picks his 12 favourites from his Sacred Modernity book.

With 139 photographs of 100 churches, McGregor Smith created the book to showcase the sculptural and unique forms of some of the churches built in the post-war period in countries including Italy, Germany, Austria, Poland and the UK.

Published by Hatje Cantz with essays by writers Jonathan Meades and Ivica Brnic, Sacred Modernity: The Holy Embrace of Modernist Architecture aims to bring attention to the unconventional buildings.

"Many are surprised to discover the thought-provoking nature of brutalist architecture and are drawn to its challenging and unconventional qualities," McGregor Smith told Dezeen.

"In essence, the experience of encountering brutalist churches often involves a transformation from scepticism to appreciation, as individuals are confronted with the unique beauty and architectural innovation that these structures represent."

McGregor Smith recalled that his work on the book began when he visited the brutalist Wotruba Church in Vienna, which sparked his interest in modernist church architecture. Since then, he has been driven to discover more churches like it.

"One of the driving forces behind my project was the realisation that many of these remarkable spaces were not fully appreciated within the architectural community and often remained unknown to their local populations," said McGregor Smith.

"I felt a sense of excitement and purpose in rediscovering these hidden gems that so freely express creativity," he continued. "These architectural marvels evoke within me a profound sense of awe and curiosity, thanks to the architects' masterful use of form and light."

The churches in Sacred Modernity have sculptural concrete forms that break away from the mould of conventional churches, which typically have a floor plan in the shape of a cross.

McGregor Smith claimed this was part of a trend after the second world war, which sought new styles separated from traditional architecture of the past.

"While traditional churches evoke a sense of familiarity and reverence through their classic designs, brutalist and modernist churches challenge these norms with their bold, austere and provocative aesthetic," he said.

"These architectural styles emerged in the post-war period as a rejection of the past's orthodoxy and a pursuit of a new social order free from associations with opulence, authority and war."

"In response to the reformed liturgy following the Second Vatican Council, church commissioners were granted unprecedented freedom to depart from traditional church typology," McGregor Smith continued.

"They eschewed nostalgic replication, resulting in spaces that excluded functional areas and symbols prevalent since medieval times, retaining only the essential elements of the altar, cross, and font."

He explained that while early modernist churches adopted familiar rectangular or cross shapes, they quickly evolved to incorporate different geometries such as squares, circles and octagons. Many relocated the positions of altars, which would usually be situated at the top of the cross-shaped church, to the centre of the building.

McGregor Smith also described that modernist and brutalist churches exhibited a move away from traditional forms of religious symbolism in decorative elements, and instead used the material and shape of the building to recall the same feelings.

"Traditional mediums of painting, craft, and sculpture, which once adorned medieval and baroque churches to elevate divine power and beauty, gave way to weightless abstract forms made possible by steel and reinforced concrete," he said.

"This departure from traditional symbolism shifted creative expression away from supernatural narratives of heaven and hell, embracing instead earthly qualities of materiality," McGregor Smith added.

"Sanctuaries assumed primordial cavern-like forms, reflecting the inherent qualities of earth and stone, while industrial and military architectural influences transformed church interiors into bunker-like shelters."

Below, McGregor Smith highlights 12 of his favourite churches from Sacred Modernity:

St Reinold Kirche in Düsseldorf, Germany, by Josef Lehmbrock (1957)

"This small unassuming church has an austere yet majestic beauty that defines how simple design and materials can create subtle elegance.

"Although narrow, the shuttered windows create depth and volume providing a calming soft light that hints at the vastness of space beyond its walls."

Santuario della Beata Vergine della Consolazione in San Marino, Italy, by Giovanni Michelucci (1967)

"Giovanni Michelucci has sculptured a splendidly creative and joyful interior that celebrates simultaneously the organic and supernatural.

"The form nods to the sanctuary cave and the symbolism of new life represented by the egg. The unreachable windows and walkways invite visitors' eyes to explore and contemplate mysteries."

St Mauritius Kirche in Munich, Germany, by Herbert Groethuysen (1967)

"Germany's post-war churches are often brutal and austere. Their designs reflect a rejection of the opulence and pride of the pre-war period and serve as a place of sanctuary and reflection.

"Stripped of their symbology and place in time, they are spaces to forget the horrors of history, war and shame and focus on the hope and light of the future."

St Paulus Kirche in Neuss-Weckhoven, Germany, by Fritz Schaller, Christian Schaller and Stefan Polónyil (1968)

"Here the concept of incarnation is integrated through the abstraction of organic forms and geometry as a sacred message. The omnipresent roof structure serves as a conduit, forging a connection between the celestial and physical realms.

"Working with his father, this was Christian Schaller's first commission after qualifying, and I had the pleasure of asking him personally for permission to include this image as the book cover."

Osterkirche in Oberwart, Austria, by Gunther Domenig and Eilfried Huth (1969)

"Perhaps the most radical church in Austria, the building shows all the signs of a culture excited and influenced by the science fiction of the day.

"It is at once ancient and futuristic, a medieval cavern furnished for the space age. This was an unexpected discovery early in the project – a beautifully serene sanctuary and a personal favourite."

St Matthäus Kirche in Düsseldorf, Germany, by Gottfried Böhm (1970)

"A lesser-known work of Gottfried Böhm's, this church's cavernous interior cascades above you, interspersed with interjections of sculpturing light.

"Symbols of industrial architecture, such as the rounded ovens, represent the Ruhr region's manufacturing heritage and of the furnaces that reside at the base of humanity."

Chiesa di San Nicolao della Flue in Milan, Italy, by Ignazio Gardella (1970)

"Like the skeleton of a whale or Christ's embodiment, the ribbed ceiling appears to hold the weight of the world above you.

"While the artwork and organ appear teleported from a previous century, the basilica's traditional frame is given a futurist interpretation using novel engineering."

Chiesa di Santa Maria della Visitazione in Rome, Italy, by Saverio Busiri Vici (1971)

"Perched high up amongst the alpine hills, the winding journey through Austria and Italy made the visit to this church evermore special.

"It was built as a memorial church to commemorate the loss of over 2,000 local people and their parish church, who were killed and swept away when a landslide breached the dam in the mountains above the town. The shape of the church emulates the curve of the damn wall, the flow of water and perhaps a stairway to heaven."

L'église Saint-Nicolas in Heremence, Switzerland, by Walter Maria Förderer (1971)

"Maria Förderer's chaotic and abstract expressionism illustrates an ethereal reality beyond our earthly experiences.

"The theological idea of the apathetic is considered here, where divinity cannot truly be considered with the known language or ideas of human existence."

Cathedral Church of Saints Peter and Paul in Bristol, UK, by Ronald Weeks, Frederick Jennett and Antoni Poremba (1973)

"Perhaps the UK's finest example of modernist sacred architecture, Ronald Weeks has created an extraordinarily rich atmosphere in the Cathedral Church of Saints Peter and Paul, choosing form over liturgical function.

"Architecture critic Jonathan Meades described the church thus: 'The last of the [UK] mega-churches, Clifton Cathedral seems embarrassed by its function, but the building would rather be the national theatre. Its brute, board-marked concrete and jagged discords come straight off the Southbank.'"

Heilig-Kreuz-Kirche in Vienna, Austria, by Hannes Lintl (1975)

"Hannes Lintl adopts an overbearing mix of structural form and light design to reflect the power and omnipresence of the divine.

"This concrete 'bunker' offers visitors sanctuary and security, guiding visitors along a clear path towards spiritual enlightenment."

Kościół świętego Dominika in Warsaw, Poland by Władysław Pieńkowski (1994)

"Too recent to be described as post-war, this Polish church can rather be considered post-soviet. Church construction during the Russian occupation of Warsaw was almost entirely banned, influencing the flourishing of sacred architecture that followed independence.

"This church reminds one of the vaulted medieval churches of France and Britain, yet its geometry and tunnelling light give it a timeless energy."

The photography is by Jamie McGregor Smith.