Giuseppe Verdi was the finest of all Italian opera composers of the 19th century, and arguably the finest opera composer of any nationality or period. Born into a family of small landowners near Parma in Northern Italy, he showed some musical ability at an early age, but when he applied to study at the Milan conservatory he was turned down. Undaunted, he studied privately, and soon became "town music master" in the small town of Busseto. His first opera Oberto was premiered successfully at La Scala in Milan in 1839.

When he was 23 he had married, but in 1840 his wife and their two children all died in quick succession. Verdi was distraught, and nearly gave up composing altogether, but a libretto for Nabucco caught his attention. Produced to huge acclaim in 1842, this opera with its famous chorus of Hebrew slaves Va pensiero established his reputation not only in Italy but across Europe. Over the next 10 years there followed a succession of fine operas, some on literary themes and some political, which culminated in his great trilogy of popular works La Traviata, Il Trovatore and Rigoletto.

By this time Verdi was sharing a house with the soprano Giuseppa Streppani; this relationship caused much scandalous gossip which they serenely ignored, though they eventually married in 1859. It does, however, show Verdi's willingness to flout the morals and conventions of his time.

He continued to create a stream of fine operas, though not as rapidly as before; one reason for this was his involvement in politics. After hundreds of years as a patchwork of rival states, Italy was becoming unified under the king Victor Emmanuel, supported by Garibaldi. At this time a nationalist slogan appeared: "Viva VERDI"; "Viva Victor Emmanuel Re D'Italia" (Long Live Victor Emmanuel, King of Italy). Perhaps Verdi was fated to get involved in politics!

The operas at this time were his mature masterpieces such as The Force of Destiny, Don Carlos, A Masked Ball, Aida, and finally in his old age Otello and Falstaff. These last two show Verdi's lifelong love of Shakespeare; he had written an opera on Macbeth as a young man, and long toyed with setting King Lear. Both are great works, and Falstaff is an amazingly vital and humorous work for a man of 80 years.

In his old age Verdi put some of the money he had made form his music to charitable causes, funding a hospital for poor labourers near his country house, and a home for retired musicians in Milan. Verdi died in 1901 within just a few days of the death of Queen Victoria in England. The Italians felt the loss of their beloved composer quite as much as Britain felt the loss of its queen - 28,000 people lined the streets of Milan for his funeral.

This year, 2001, being the centenary of Verdi's death, is seeing many performances of his works, and a reassessment of his place in musical history.

Verdi's love of literature was not restricted to Shakespeare; he also loved with a devoted passion the work of the contemporary writer Alessandro Manzoni. Manzoni's greatest novel I Promessi Sposi (The Betrothed) is set in 17th century Lombardy (Northern Italy) when it was under Spanish rule: it was easy for his 19th century readers to relate it to their own time, when Lombardy was under Austrian rule. Verdi's admiration for Manzoni amounted to hero-worship, and despite his own great fame, Verdi was in complete awe of the older man.

When Manzoni died in May 1873, Verdi decided he wanted to honour the great man with a Requiem Mass, to be performed on the anniversary of Manzoni's death. The authorities in Milan agreed to the project, Verdi wrote his score with rapid fluency, and the Requiem was duly performed in the church of San Marco, Milan on 22nd May 1874, a year to the day after Manzoni's death, with Verdi himself conducting. His forces comprised soloists from La Scala opera house, a chorus of 120 singers (small by modern standards) and an orchestra of 100 (which must have drowned out the choir considerably!). Performances in La Scala soon followed, and were hugely successful, with several of the movements being encored. Further performances in Italy and Europe soon followed, and while some listeners thought the work too overtly emotional for supposedly sacred music (this view particularly held sway in Victorian England) its direct appeal soon won over the hearts of most of the musical public.

The Requiem is scored for four solo singers, choir and a normal orchestra, though there are four bassoons to strengthen the bass line, four extra trumpets to add power in the Tuba Mirum section, and a notable solo part for the bass drum. The writing is dramatic and operatic, full of emotion and of contrasts, with a range of dynamics from a shattering ff down to an inaudible pppp. As well as its direct appeal, it is also a subtly constructed score, with many thematic links and cross-references which reveal themselves only on close study and careful listening.

Verdi based some of the Requiem, in particular the final movement, on a Libera Me he had written a few years earlier for an abortive requiem in memory of the composer Rossini. This was a collaboration between 13 different composers, but although all the separate movements had been written, for a variety of reasons - e.g. the work was only to be performed on the anniversary of Rossini's death, no-one was to make a profit from it, the disparate styles of the movements - the project was never brought to a performance.

1. Requiem and Kyrie
The Requiem opens quietly, with the choir's subdued pleas for rest for the departed - Requiem aeternam dona eis, domine. There is an abrupt key change into the next section (Te decet hymnus) which gives the unaccompanied choir a chance to show what it can do; the soloists soon get a chance to shine too in the Kyrie, the words of the standard opening to the mass (Lord have mercy, Christ have mercy). The movement ends quietly.

2. Dies Irae
Four colossal thunderbolts from heaven release the Dies Irae, a tempestuous vision of the fury of the day of judgement (Dies Irae, dies illa) - the day of anger, the day of wrath, when the prophets' warnings of final judgement are realised. You can't fail to notice how, when the four thunderbolts strike a second time, they are echoed from the earth by the bass drum. This subsides into fearful mutterings, which are soon interrupted by the distant trumpets of the Tuba Mirum. These are the trumpets that summon the legions of the dead to appear before their maker. Following a huge climax ending on a high shriek, the bass comments that even death itself is stunned by this summons (Mors stupebit). Then in Liber Scriptus the mezzo-soprano tells how all of our deeds have been recorded and will be remembered at this day of judgement (Liber scriptus - it is written). It is a terrifying prospect - nothing will be missed in this record (nil inultum - nothing forgotten) - and leads to a repeat of part of the Dies Irae section.

A pause follows, and two clarinets lead into a duet for the mezzo-soprano and bassoon Quid Sum Miser. Here the soloist asks Who will plead for me on my behalf, in front of the divine judge? She is soon joined by the soprano and tenor, which leads into a vision of the dread judge himself - Rex Tremendae. This alternates the awesome (Rex tremendae) and pleading (Salva me - save me). The Recordare follows without a break, a duet for soprano and mezzo, in which they remind us of Christ's dying on the cross for our salvation - was this all in vain? It would be indeed a hard judge who could resist pleading of this insinuating beauty.

After a pause, the tenor soloist adds his voice in a gloriously operatic aria expressing repentance for sins, and asking to be forgiven (Ingemisco). The bass is more direct; he requests When the wicked are consigned to the flames of hell, may I be blessed and saved (Confutatis maledictis). This leads back to a recapitulation of the Dies Irae section, almost in its entirety. Finally, all the soloists and chorus join in a final expression of grief (Lacrymosa) and hope that the gentle Lord will grant rest to the dead (Pie Jesu, Domine, dona eis requiem). An unexpected cadence in the last few bars is like a shaft of sunlight across the fears and shadows we have experienced.

3. Offertorio
This begins with a glorious soaring melody in the cellos, to reveal a movement in which the chorus is not used, only the soloists. The opening and ending are a plea to Jesus to free the souls of all the faithful from the torments of death (Libera anima). After this comes a more vigorous section (Quam olim Abrahae), leading into the central section (Hostias) which is a beautiful and delicate prayer. Starting on the solo tenor, it has the most transparent of orchestral accompaniment. A repeat of the Quam olim Abrahae section leads to a climax, and the movement ends with the Libera anima music with which it began.

4. Sanctus
Holy, holy, holy, .. Heaven and Earth are full of Thy glory! The Sanctus could hardly be a greater contrast to the peaceful Offertorio. It is a vigorous double fugue for the chorus, who are divided into eight parts instead of the normal four, and is loud and energetic throughout. Verdi gives the orchestra a good chance to share in the fun too.

5. Agnus Dei
Again, a dramatic contrast to the previous movement. Where that was loud and fast, this is calm and peaceful. It begins liturgically, as the soprano and mezzo intone a unison chant (Lamb of God that takes away the sins of the world, grant them eternal rest). This is immediately repeated in unison by chorus and orchestra. Notice how, when the opening is later repeated, the two soloists are accompanied only by a beautiful trio of flutes.

6. Lux Aeterna
The Lux Aeterna (Let perpetual light shine upon them, Lord) is introduced by the mezzo-soprano, surrounded by a glowing shimmer of strings, followed by the bass in a dark B-flat minor. The movement unfolds as a trio for soloists, emphasising the contrast of darkness (sombre brass chords) with light (airy, floating woodwind patterns). The end is serene.

7. Libera Me
The last movement is more complex - this is the movement Verdi wrote for the failed 'Requiem for Rossini' project, and he crammed a lot into it. Of the four soloists only the soprano sings here - the other three are silent. It begins as an urgent chant (Libera me, domine, de morte aeterna - Lord, free me from eternal death) with hints of the terror of the Dies Irae. At the words Tremens factus sum ego (I am full of terror) we feel the earth beginning to sway beneath us, and a brief pause leads to a full restatement of the Dies Irae section from earlier. This subsides into a section for chorus and soprano alone (Requiem aeternam), based on a section at the very opening of the work when it was set for strings. It ends with the soprano soloist soaring (as quietly as possible!) up to a high B flat. Another chant leads into the second major section of the movement - a determined fugue of great energy and drive for the chorus and orchestra. The soprano soon joins in, and Verdi alternates the energetic fugue with the falling Requiem aeternam theme. This works up into a huge climax, after which the entire Requiem ends in calm with the almost spoken prayer - Libera me.