AS NATIONS, they appear as different as the landscapes which nurture them. On the one hand there are the Italians, warmed by the Mediterranean sun, open, impulsive, excitable; as emotionally volcanic as Mount Vesuvius. On the other, there are the Welsh, dour, rainswept, closed; their emotions locked behind barriers as forbidding as the rock-strewn slopes of their protective mountains.

Their temperamental differences are vividly illustrated by their religions. While the Welsh flocked to spare, white-walled chapels to express their love of God in dark hymns laced with the bloody imagery of the crucifixion, the Italians gathered in churches packed with sensuous decoration and works of art which proclaim their love of the human form, especially the figure of a voluptuous women.

While the chapel minister thundered hellfire and damnation severe in sober suits and stiff, white collars, the Italian priest wrapped himself in rich robes and the smoke of burning incense to drive home his easeful message of forgiveness and salvation.

Sometimes the differences have spilled over into venomous hatreds. For nonconformists during the 19th and much of the 20th centuries, Roman Catholicism was little more than modern paganism and the Pope, anti-Christ.

The feeling sometimes triggered violence and anti-Catholic riots. My ancestors were victims of such religious antagonisms. When they had the temerity to open their cafes in the South Wales Valleys on Sundays, they found the full fervour of Evan Roberts's revival in 1904-1905 was turned against them. Crowds marched on the Italians to force them to close their doors.

The tail end of those feelings affected my childhood. I vividly remember the fights involving hundreds of my schoolmates that regularly broke out between my Dowlais Catholic school and the Protestant secondary modern on the hill overlooking us.

But these obvious differences mask similarities close enough to suggest the Welsh and Italians form part of the same family, even if their separation in terms of distance and climate sometimes make them quarrel. In the words of journalist Rene Cutforth, "the Welsh are the Italians in the rain".

Physical stereotypes suggest a resemblance between the races. Characterising the Welsh and the Italians as "small, dark and mercurial" may be dangerous since each has as many exceptions - tall, blue-eyed and blond - as there are examples proving the rule. But I have been struck by the resemblance between my family and the Welsh.

During one National Eisteddfod I bumped into a stranger who looked so much like a dead uncle I had to bite back a greeting. There is a basis in history for those resemblances. Almost yearly, archaeology reveals the strength and the richness of the Celtic culture which once dominated that part of Northern Italy from which my family came. And the dialects spoken all over north of Italy carry the linguistic label, Italo-Celtic, to mark the influence of ancient Celtic languages on them.

The arrival of the Romans in 43AD exercised a profound influence on the Celtic Britain that preceded the Welsh nation. By the end of their 400-year stay they created a new way of life. Their influence remains in the vocabulary of the Welsh language. It carries many words borrowed from Latin.

The Romans introduced Celtic Britain to the wonders of straight roads, new systems of crop rotation, new fertilisers and better ploughs. They introduced the Celts to the delights of writing and of urban living.

From the Romans, the Celts learned new religions, how to mine gold, how to live in large country villas and to use the improved methods of farming that came with them. Much of that impressive civilisation was buried beneath the chaotic and violent Dark Ages that arrived in the wake of the barbaric Angles, Saxons and Jutes.

Despite, or perhaps because of, the long years of armed struggle against the English, the Welsh never forgot their ties to Roman civilisation. Indeed, one Spanish-born Romano-British general who became Emperor is often credited with being the father of the Welsh Nation.

Many of the most powerful Welsh royal families claimed to be descended from Magnus Maximus, Macsen Wledig, who took control of the Empire through his revolt of 383AD.

The cultural, artistic and religious connections between Italy and Wales continued. In the wake of the 16th century Reformation, for example, Welshmen who stubbornly clung to the old religion - men like Owen Lewis and Morys Clynnog - helped to establish a Catholic seminary in Rome.

There, priests were trained for the dangerous job of ministering to the Catholics courageous enough to cling to their faith in Protestant England and Wales.

Clynnog and Lewis helped to publish Catholic books which were smuggled into Wales. One, written by Morys Clynnog, was the only book about Catholicism written in Welsh in the 16th Century.

There have been strong artistic links between the two countries. One of the best Welsh painters of the early 19th Century, Penry Williams, spent much of his productive life studying and working in Italy. Williams, the son of a house painter, was born in Merthyr Tydfil in 1800. His talent flourished under the patronage of the local ironmasters.

He left for Italy when he was 22 years old. His exciting pictures of life among the inferno of furnaces and puddling sheds in the ironworks were replaced by glowing, idealised portraits of sleek Italian peasants.

In the 20th century, poets such as Dylan Thomas and John Ormond had strong links with Italy. Dylan Thomas spent several months living in Florence. Italian patrons supported his poetry.

A delight in the power and the beauty of the human voice unites the two nations. That great Welsh singer, Sir Geraint Evans, studied in Italy, perfecting vocal and acting techniques.

Appropriately in the light of today's international match, there are strong links between rugby union in Wales and Italy. Several Welshmen have played key parts in the development of the Italian game. Two, Roy Bish and Gwyn Evans, coached the Italian national side.

The charismatic Carwyn James was hugely influential in shaping Italian rugby during the years he spent as coach of Rovigo. A number of Welsh players have carved out careers for themselves in Italy, including the former Wales and Ebbw Vale back-row forward, Clive Burgess.

The political cultures of the two nations are entwined. The fact that Italy is a young nation which achieved political unity late and against great odds has proved inspirational for many Welsh nationalists.

The philosophy of Giuseppe Mazzini, the father of Italian unity, exercised a powerful influence on Welsh thinkers. A few decades later, the writings of the Italian communist and nationalist, Antonio Gramsci, would profoundly affect left-wing intellectuals in Wales.

The Italians and the Welsh share a delight in the attractions of opera and poetry. That gloomy intensity and preoccupation with the horrors of the crucifixion is as much a trademark of Italian religious seers and saints as it is of Welsh nonconformists.

And the Welsh can celebrate the sensuous joys of life with as much verve as the Italians. Dafydd ap Gwilym can teach the Italians a lesson or two when it comes to praising the delights of sex and wine.

Some of Penry Williams's later paintings of Italians match anything the Italians could produce when it comes to idealising the simple beauty and strength of Italian peasant culture.

My own family is proof of the ability of the Welsh and the Italians to share and to enrich each other's cultures. Almost from the moment my predecessors arrived in Wales to run their cafes and fish and chip shops, they found themselves at home, relishing the curiosity, the emotional openness and the love of family they shared with their hosts.

They have since integrated perhaps a little too seamlessly into the Welsh way of life. Education and intermarriage threatens what remains of the tradition Welsh-Italian culture. Its loss would be tragic.

I have a strong feeling that the teams in today's international will display the same sense of adventure and honesty and commitment. But however close their styles and their approach, may they never become too similar.

To borrow a French phrase and mangle it into Italian - Viva la nostra diversita, Long live our differences!