Under the new municipal government model that was imposed following the Bourbon triumph in 1714, Sants became detached from the city of Barcelona administratively, with the goal of weakening the Catalan capital. The first municipal government of Sants was constituted in 1721. Before the 1713-1714 siege, Sants was formed by 39 houses and had a population of 153 adults. After the devastation caused by the war, the 1715 census recorded only 92 people living in the area.

One of the first battles in the siege of Barcelona took place at the Capuchin Convent of Santa Madrona when, on 8 September 1713, a 3,000-strong Bourbon force attacked the fortified monastery, capturing the site after two days of constant fighting. The response from the besieged forces was a persistent bombardment from Montjuïc Castle, which went on until September 16. The monastery was left in ruins, but in the hands of the assailants, who had advanced a couple of hundred metres. A few weeks later, the Austrian forces turned the tables on their Bourbon foes by launching an attack against their stronghold at Can Navarro. The following January saw the most daring skirmish in the campaign when the Miquelet company, led by Josep Marco i Ferrís, el Penjadet, attacked the Spanish army encampment at Can Safont. This attack achieved its purpose of causing the Bourbon troops to retreat in disarray and, a few days later, on 26 January 1714, commander-in-chief Antonio de Villarroel ordered an offensive against the Bourbon line surrounding Barcelona. After this, there was little fighting in the area. After the surrender of the city, gallows were erected in the centre of the new-constituted municipality of Sants, from which those found guilty of possessing weapons were hanged.

The group of farmhouses grouped together as Les Corts was a territory free from all subjection to a lord and, with Sant Just Desvern, formed Les Franqueses del Llobregat. This community was an autonomous civil quarter under the jurisdiction of the local mayor, a post that was appointed by the Royal Audience after the Decree of Nova Planta (1716) entered into effect. Les Corts was under the ecclesiastic jurisdiction of the Parish of Sant Vicenç de Sarrià, with its own representatives. This local system lasted until the 1812 Constitution became law.

Two days after the end of the Bourbon siege, on 14 September 1714, four representatives —two from the Generalitat and two from the Council of One Hundred— went to one of the noble mansions in Les Corts, the Can Feló farmhouse, where the Duke of Berwick had his headquarters, to sign the surrender. However, Marshal Berwick agreed to receive only Josep Antoni de Ribera i Claramunt and Anton Massanés i Reverter, the representatives from the Council of One Hundred, who requested his permission for them to send two commissioners to Madrid and that the councillors might attenuate the conditions of the capitulation. Marshal Berwick replied that, in three days time, he would form the new city government and that, therefore, municipal government would no longer be in the hands of the Council of One Hundred.

Sarrià was the largest and oldest village on the Barcelona plain, and had enjoyed royal protection since the 14th century, although its municipal government was not constituted until a century later. After the Bourbon siege of Barcelona (1713-1714), Sarrià had a population of 674, with 224 houses, including the farmhouses in the Les Corts area. Under the Decree of Nova Planta (1716) Sarrià, Les Corts and La Travessera were grouped into a single, complex local authority in which all three populations were represented.

With a six-month difference, both pretenders to the Spanish throne launched attacks against the former Torre Lledósite: on 15 October 1705, Archduke Charles, and in April 1706, Philip V. On 13 September 1705, a large group of noblemen (Antoni Meca i de Cardona, Gaspar de Berart i de Cortada, Francesc Amat, Carles de Ribera i Claramunt) had gathered in Sarrià in support of the Austrian archduke. A few days later, Barcelona Military Junta was established to support operations in the Austrian siege of the city.

The first official meeting between the Catalan institutions and Archduke Charles took place on 19 October 1705 at the Capuchin Convent of Santa Eulàlia in Sarrià. Those at the meeting were two representatives from the Council of One Hundred, two from the Generalitat and the chief of the Austrian forces, Prince Anton Florian of Liechtenstein. The business discussed included various military issues and other, deeper political matters, such as the convening of the Courts, protocol with regard to hand-kissing and the archduke’s entry into the city, and the terms in which the Catalan institutions would write to their allies to inform them of their intention to swear loyalty to Archduke Carles.

On 6 April 1706, during the first Bourbon siege, the army of Philip V, led by the Count of Tesse, occupied the Royal Monastery of Santa Maria de Pedralbes.

Unlike other villages on the Barcelona plain, Gràcia was under the Catalan capital’s jurisdiction until 1850.

Prince Georg Hessen-Darmstadt, popularly known as Jordi since his period as viceroy of Catalonia (1698-1701), was buried in the Convent of Santa Maria de Jesús in Gràcia, known as the Josepets’ convent. Prince Jordi was wounded during the Austrian siege of Barcelona when he led his men in an attack on Montjuïc. His death a few days later, on 13 September 1705, caused great commotion in the city, for he was dearly loved amongst the population.

The failure of the first Bourbon siege of Barcelona led to the hasty withdrawal of Philip’s troops on 12 May 1706. In their flight, these armies left one hundred and forty artillery pieces on the battlefield. The siege had left nine thousand dead and one thousand five hundred wounded amongst the assailants, and these were abandoned in the Capuchins’ convents of Sarrià and Gràcia. The Capuchins’ Convent of Montcalvari was converted into a Bourbon hospital to treat over one thousand wounded. Twenty years later, during the second Bourbon siege, the convent had been converted into an Austrian stronghold outside the city walls. The Duke of Popoli ordered a siege to be laid against the site on 12 May 1714. The defenders managed to hold off these attacks for a week, but finally fled, taking refuge in the Franciscan Convent of Santa Maria de Jesús in Gràcia. From there, on 5 August 1714, an unsuccessful attack was launched against the Convent of Montcalvari.

Horta was awarded township status as a consequence of the implementation of the new Spanish municipal system imposed under the Decree of Nova Planta (1716).

In spring 1709, Archduke Charles and his wife, Elisabeth Christine spent a long period at the palace of the Austriacist Ignasi Fontanet, a site that later became known as Can Fontaner.

During the Bourbon siege of Barcelona (1713-1714) the encampment closest to the battle zone was at Mas Guinardó, where, firstly, the Duke of Popoli and, later, the Duke of Berwick took up residence. The origin of the name of this farmhouse derives from the old Catalan word guinarda, meaning fox; some, however, attribute the name to Miguel de Cervantes, who lodged here during his visit to Barcelona and insisted that the farmhouse was under the control of the bandolier Perot Rocaguinarda.

Six hundred fusiliers and the soldiers from the Fe and Sant Jordi (“Faith” and “Saint George”) regiments, commanded by colonels Ermengol Amill i Manuel Moliner —who had been abandoned by their fellow officers in the expedition led by Antoni Francesc de Berenguer, Generalitat military deputy— attacked the Bourbon cordon in the Guinardó zone on 6 October 1713, and some three hundred and eighty managed to enter Barcelona under cover of artillery fire provided by the defenders inside the city.

On Christmas Eve 1713, Bourbon troops attacked one of the advance positions held by Austrian forces on the slopes of Mount Montjuïc. Captain Baldrich Grange repelled this assault, and Colonel Ermengol Amill planned a revenge operation, ordering reconnaissance of enemy positions in the Guinardó zone in the hope of launching a surprise attack against the Bourbon forces from the other side of the city. After inspecting the area, commander-in-chief Antonio de Villarroel authorised the operation planned by colonels Amill and Moliner. Two hundred and fifty fusiliers assembled at the Capuchins’ fortress and the two officers launched the surprise attack against the Bourbon forces quartered in Mas Guinardó. Whilst Amill led his men on the right flank, Moliner cut off the retreat to the left, a movement that disconcerted the Bourbon troops so much that they fled in disarray. Amill and Moliner’s men behaved ruthlessly towards the Bourbon soldiers, and only the lives of the youngest men were spared. They spent an hour sacking the enemy camp, setting fire to the site before withdrawing. The operation was an almost unqualified success: the enemy troops were disorganised and had suffered a severe blow to morale; a trail of blood and destruction had been left, and Austrian forces had suffered just eight dead and eleven wounded.

Sant Andreu de Palomar had been a rural community under the jurisdiction of the Council of One Hundred, the government of Barcelona, since medieval times. According to the 1716 census, Sant Andreu had a population of 600, dispersed over the large area between the main centre, around the Parish Church of Sant Andreu and a second nucleus near the Church of Santa Eulàlia de Vilapicina, and many scattered farmhouses. In the local political organisational model imposed under the Decree of Nova Planta (1716), Sant Andreu had its own local authority, separate from the Barcelona administration.

In May 1704, most of the Austrian forces that had disembarked at the mouth of the River Besòs were quartered in Sant Andreu, and skirmishes broke out in Santa Eulàlia de Vilapicina when Bourbon troops tried to break the siege of Barcelona. Sant Andreu provided large contingents for the Vallès militia forces that attacked Philip V’s army as it passed through Torre del Baró, and the king later took reprisals against the town. In August 1705, the leading citizens of Sant Andreu swore allegiance to Archduke Charles, who had just disembarked, at the Cal Borni farmhouse. A few months later, the tables were turned, and Sant Andreu was occupied by the Bourbon army of Duke of Noailles, then laying siege to Barcelona.

In May 1709, Archduke Charles inspected the troops of the Royal Catalan Guard Regiment in Sant Andreu. The Bourbon troops began a new siege of Barcelona in July 1713, establishing one of their main centres of operations in Sant Andreu, on the estate known as the Torre dels Pardals, near Guinardó. Here, barracks were built, a powerful artillery battery was installed and an advance lookout post was used, firstly, by the French high commander the Duke of Popoli and, later, by the Duke of Berwick during the final stage of the siege in the summer of 1714.

Before the War of the Spanish Succession, this township was governed by a local authority that did not have its own resources, and was forced to rely on economic aid from the parish. According to the 1717-1718 census, the local population stood at 177, but this number increased exponentially over the course of the 18th century due to the opportunities offered by farming and the burgeoning manufacturing industry. Before the war, El Clot neighbourhood comprised just three or four scattered houses.

On 3 April 1714, the Spanish troops in the Bourbon army set up a battery of heavy mortars in El Clot. From here, they began to bombard the city. On April 4, the besieged forces began to reply with constant artillery fire that managed to silence the mortars within six days. A few weeks later, the El Clot encampment was the site of a meeting between Sebastià de Dalmau, emissary from the Barcelona Governing Junta, and the French Minister Jean d’Orry in order to seek a negotiated settlement to the siege. Although Dalmau was in favour of ending the war, the Junta took a more belligerent stance, making it impossible to reach an agreement with Jean d’Orry.